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S i g n a t u r e s Newsletter of the Indian Society of Remote Sensing –Ahmedabad Chapter Volume: 23, No.1 & 2 January - July 2011

Special Issue on Industry Contributions to Remote Sensing Activities S i g n a t u r e s Newsletter of the Indian Society of Remote Sensing –Ahmedabad Chapter

Volume: 23, No.1 & 2, January - July 2011 Special Issue on Industry Contributions to Remote Sensing Activities

Dedicated to Dr. Vikram A. Sarabhai Father of Space Sciences in India

on his 92nd birth anniversary

August 12, 2011

being celebrated as the

National Remote Sensing Day Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Inside this Issue

1. Messages 2. Preface 3. Acknowledgements 4. From the Chairman’s Desk 4

Theme Articles 1. An Interview with President, ISRS 5 2. RS Applications Software & Services 10 a. Industry Contributions in International Remote Sensing Activities of Antrix 10 b. Industry Participation in Remote Sensing, Scanpoint Geomatics Limited 15 c. Increasing Role of Private Industry in Remote Sensing Activities, Mr. Jiping Li 18 d. GIS and Remote Sensing Applications Related Services from CompuSense Automation 20 e. Using Commercial Software to Enhance Commercial Imaging Acquisition, AGI 20 f. Services and Innovative Technology Development by Globaltech India , Ahmedabad 25 3. RS Payload Hardware a. An Interview with Managing Director, Centum Electronics Limited 28 b. Electro-Optical Sensors 34 i. Multispectral and Hyperspectral Sensors for Remote Sensing, Teledyne DALSA 34 ii. Hyperspectral CMOS Imager, e2V 39 iii. Latest Developments in Infrared Space Detectors at Sofradir 44 iv. 3000 Pixel Linear InGaAs Sensor for the Proba-V Satellite, sInfraRed 57 v. Single Photon Detection Using InP/InGaAs Avalanche Diodes, Princeton Lightwave 61 vi. SAGEM – REOSC contribution to Indian Remote Sensing Programs 66 vii. Overview of Teledyne Judson Technologies Contribution to Remote Sensing 72 c. Microwave Sensors i. Industry Role In ISRO’s Microwave Remote Sensing Payloads, NM Desai 83 ii. Real-Time Spectrum Analysis Reveals Time Domain Characteristics of Microwave Signals, Tektronix Inc. iii. Digital Radar Receiver System (DRRS) - A case study from Mistral Solutions Pvt. Ltd. 93 iv. Contributions of K.V. Microwave Materials, Ideal K.V. Microwave Products and Sahajanand Laser Technology Ltd. to Remote Sensing Activities 97 v. Measurement the Quality of Chirp Radar Pulses using Impulse Response (Time-Sidelobe), Tektronix Inc. 100 d. An Interview with Managing Director, Astra Microwaves Products Limited 106 e. Electronics Subsystems for Electro-Optical & Microwave Payloads 110

1 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 i. Design, Development and Delivery of Space grade Modules and Subsystems for Remote Sensing applications from Centum Electronics 110 ii. Contribution to Space Projects by Astra Microwave Products Ltd. 115 iii. The ever increasing complexity of PCB layout, CMR Design Automation Pvt. Ltd. 118 iv. Komoline’s Journey into India’s Space Sector 122 v. Ambimat’s Contributions in Space Activities 125 vi. Integrating Relationships 129 vii. Engineering Capabilities of Spur Microwave Inc. 130 viii. Data Patterns’ Participation in Space Programme 132 ix. Xilinx FPGAs: the X-link of Space Applications 135 x. FPGA & ASIC Design Services from CoreEL Technologies 139 xi. Digital Signal Processing Unit for Space Use 143 f. Product Development Tools 148 i. Product Development System With PTC Windchill, Adroitech 148 4. RS Satellite Launch & Test Facilities 154 a. Taking Part In Indian Space Dream, Shell-N-Tube 154 b. Upgradation of Instrumentation Control & Data Acquisition System for 5.5m Thermal Vacuum Chamber, by Prima Automation (India) Pvt. Ltd. 158 General Articles 1. Payloads for Resourcesat-2, H. K. Dave 161 2. Microwave RS Signatures of Precipitation and its Retrieval over Land and Oceans- R.M. Gairola 167 Regular Columns 1. Member News 181 2. Readers’ Views 181

3. Chapter News: • A Brief Report on 12th Prof. Pisharoty Memorial Lecture by Prof. A. Jayaraman 175 • A Brief on World Environment Day Celebrations 176 • New Members of ISRS-AC 178 • Forthcoming Chapter Activities 178

4. ISRS Updates January-June 2011 9 5. Forthcoming RS related Conferences 165 6. Snippets on Naturally & Historically Remote Sensing 31/26 7. News: DOS adopts Remote Sensing Data Policy (RSDP- 2011) 179

8. Signing Off 182

2 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 List of Advertisers

3-D Plus 141 Jaymin Engineering Pvt. Ltd. 152 Adroitec Engg. Solutions Pvt Ltd. 151 Komoline Electronics Pvt. Ltd. 124 Advance-Tech 146 Labsphere Inc. 82 Aerotech Nanopositioners 38 Liberty International Backcover Agilent Technologies 117 Maharshi Electronic Systems 128 Alligator Designs Pvt. Ltd. 147 Mistral Solutions Pvt. Ltd. 96 Ambimat Electronics 127 Optimized Solutions Pvt. Ltd. 186 Amphenol Interconnect India Pvt. Ltd. 184 Pranaav Tele-Ventures Pvt. Ltd. 142 Andhra Electronics Ltd. 137 Princeton Lightwave frontcover (I) Antrix Corporation 14 Radiall 138 Astra Micowave Products Ltd. 105 Sahajanand Laser Technology Ltd. 152 B.K. Consimpex Pvt.Ltd. 160 Scanpoint Geomatics Ltd. 17 Bryka LLC 131 Schott Glass India Pvt. Ltd. 70 Centum Electronics Ltd. 32 Shell-N-Tube 157 Chunghwa 65 SIP Tools 43 CMOS Sensor Inc. Backcover (I) Spur Microwave Inc. 121 CMR Design Automation (P) Ltd. 120 Surelia Wire-Cut Pvt. Ltd. 113 Compusense Automation 137 Syratron Marketing Pvt. Ltd. 114 Connekt Electronics Pvt. Ltd. 141 Team Technology 121

CoreEL Technologies (I) Pvt. Ltd. 150 Technocom Dies & Precison Products 153 Datatrivesystems 27 Tektronix 99 E2V 33 Teledyne DALSA 37 General Optics (Asia) Ltd. 71 Teledyne Judson 80 Globaltech India 120 Texas Instruments 145 Innovative CAD/CAM Services 153 TTL Technologies Pvt. Ltd. 137 INO/AGV Systems Pvt. Ltd. 65 Xenics Infrared Solutions 81 IRYS Elec. Engg Services (P) Ltd 131 Xilinx India 134 IT Globe Inc. . 185 Zetatek Industries Ltd. 159 Jaivel Synergies Pvt. Ltd. 151

3 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

ISRS-AC Office Bearers

From the Chairman’s Desk

Shri D.R.M. Samudraiah, Dear Members, Chairman I have great pleasure in reaching out to Prof. Anupam K. Singh, you all, the members and well-wishers Vice-Chairman of Indian Society of Remote Sensing – Smt. Parul Patel, Ahmedabad Chapter once again Secretary through Signatures. I convey my Dr. Indrani C. Singh, greetings and best wishes to all of you. Jt. Secretary In the intervening period since the last Shri K.P. Bharucha, issue was released, we had conducted Treasurer two events namely the twelfth Prof. Pisharoty memorial lecture & the World ISRS-AC EC Members Environment Day with very good participation from members.

Shri Kashyap N. Mankad This issue of Signatures focuses on the theme: Industry Contributions to Remote Smt. Arundhati Misra Sensing Activities. Signatures Editorial Team has compiled a number of Dr. Abha Chhabra interesting articles of topical interest on this theme. Several professionals from Dr. Rahul Nigam the Industry have contributed to this special issue through their brief and vivid Shri R.P. Prajapati articles on the focal theme. The technological & R&D efforts have come out very well in their articles. This issue also contains an Interview with Dr. Ranganath R ISRS-AC Office Navalgund, President ISRS & Director, Space Applications Centre, ISRO,

Ahmedabad and interviews with some of the industry leaders, apart from the

Room No. 4372, regular Columns. I thank all the authors, industry leaders, well wishers and Dr.

Space Applications Centre Navalgund for their contributions to Signatures. I believe that ISRS Members

(SAC), ISRO, Ahmedabad- and industry professionals will be extremely benefited from the information 380015. given in this issue.

Email: [email protected] Phone: +91 79 2691 4372 Oceans play a crucial role in the seasonal variations of the Earth’s atmosphere through their contributions in wind circulation, thermal currents, cloud ISRS Headquarters formation, etc. ISRS-AC is planning the next issue of Signatures on the theme- “Atmospheric & Oceanic Remote Sensing”. I request all members working on C/o Indian Institute of Remote this theme to contribute articles for the next issue. Sensing, 4, Kalidas Road, I take this opportunity to invite all of you to actively contribute to the objectives Dehradun - 248 001, India. of ISRS by taking part in the Chapter events and contributing to Signatures. Email: [email protected], Fax: +91 135 2741 987 Wishing you all the very best, Web: www.isrsindia.org

DRM Samudraiah

Theme for the forthcoming issues of Signatures: Jul – Sep 2011: Atmospheric & Oceanic Remote Sensing Oct - Dec 2011: Remote Sensing - Astronomy & Planetary Sciences.

4 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 An Interview with Dr. Ranganath R. Navalgund, President, ISRS

Signatures: Dr. also. Broadband internet services have greatly Navalgund, thank you for facilitated. sparing your time for this A large number of services which are location based interview. At the outset, services are the ones which are going to play a very how do you foresee the important role in the next few years. The situation is proliferation of the use of not very different in the world and in India. But may geo-spatial information in be in certain parts of the western countries, it has India in particular, and already reached a level where individuals are using the world in general, these location-based services in a big way, whereas considering the recent that might be just picking up as far as India is developments in the concerned. Remote Sensing, Navigation and the ICT technologies? RRN: It is actually a very comprehensive question Signatures: Generally the applications of remote sensing that you have asked. have been in aiding the Govt. and large industry sectors in Remote sensing, communication and also navigation, the decision making process pertaining to their geospatial all three are coming together in providing a large assets. What is your considered opinion about the number of services now. In addition to that, proliferation of context-aware common man geospatial developments that are taking place in high-speed solutions to the day to day problems faced by a city dweller broadband internet services are in fact facilitating or a tourist or a villager? greater use of remotely sensed data in many of the RRN: It is true remote sensing, to start with, has been applications. Remote sensing, of course, has been providing information at a much larger scale, in the progressing into very high-resolution images. It has sense for larger areas and also perhaps at a scale at also progressed in the area of hyperspectral remote which it was only useful to the decision makers or sensing, and also in many aspects of microwave the planners at the Govt. level or at the private remote sensing. But very often, we tend to think in industries, large infrastructure projects etc. But as I terms of the growth of remote sensing only as mentioned earlier, because of the advances that are applicable to the land. Whereas, if you see over the taking place in the high resolutions, as well as years, remote sensing data/observation abilities in because of the advances that are being made with the area of atmosphere as well as oceans, has also respect to weather and ocean state forecasting related considerably advanced in the last few years. It things and the availability of the GIS advances in provides a large number of measurements, which are terms of technology and the ability to convert these very important not only for weather forecasting, things and reach it to the common people that is ocean state forecasting but also in making certain what has made a difference now, whether it is a benchmarks for climate change. Developments that fisherman or it is somebody who is an urban dweller, have taken place in these areas are also being utilised who wants to do network optimization. It is still true in defining some of the sensor capabilities for that remote sensing by and large is a true aid for planetary missions. natural resources survey, monitoring and which is There is a tremendous increase in the versatility of generally used at the Govt. level or at the private big GIS services whether one talked about 2D, later on players’ level, but I think now it is transforming itself 2½ D, later on 3D, web based services and network where it could be used by the people per se. As far as analysis. I mean a host of advances that have taken communication is concerned, it is at a personal level, place in GIS have greatly benefited Remote Sensing but as far as remote sensing, one didn’t think that 5 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 way. The convergence of the synergy of the other but also the likely further areas. Emergency technologies are enabling remote sensing to become a communication is provided by satellites. In the useful thing for the common person as well. whole gamut of disaster related activities, role of space technology is yet to completely master early Signatures: What about GPS based navigation? warning/forecasting methods. And the other RRN: GPS has revolutionised navigation. A large important aspect relates to policy that makes sure that number of applications/ services which require the value added data products reach the concerned precise knowledge of position & time are centered stakeholders in a very short period of time. Third around the use of GPS. Many nations are planning relates to policy level again, of whom to give or who their own space-based navigation systems. should have the access to this information, is also very important. Signatures: What particular use do you foresee for the use of geo spatial information prior to, during or after a Signatures: Coming to the theme of this newsletter, ie., disaster in the country? industry contributions to remote sensing activities, how do RRN: Remote Sensing has many roles in disaster you assess the significance of the role of industries in situations. Pre-disaster, you would like to see the promoting remote sensing in our country vis-à-vis the hazard zonation, areas which are vulnerable to world scenario, as of now? disasters. You would also like to see and assess risk; a RRN: The way the private industries in India have particular area may be hazard prone, but only if there helped the growth of remote sensing and the allied is a habitation in that hazard zone then it becomes a services is very important. In the initial years, I think risk. So all this is possible using remote sensing and industries mostly were engaged in small jobs like GIS and this has been done for different disasters viz. digitization of the data or perhaps in making some floods, landslides, earthquakes, cyclones, or even small equipment for visual interpretation etc. But drought. So hazard zonation, vulnerability analysis soon the industries went forward and got into value and risk assessment are something which are done added products. using remote sensing and GIS that are very useful during pre-disaster. In addition to that, to a large Some of them developed a number of software both extent Remote Sensing data of land, ocean, in the area of remote sensing, GIS and image atmosphere put together and the modeling exercises processing, put them into a product including a have helped in early warning methods, forecasting computer system etc. These efforts have greatly methods; although the level of maturity of the benefited application related activities. As far as forecasting methods is not necessarily same in all building of the payloads and spacecraft themselves disasters. It has been useful in cyclone track are concerned, I think to a great extent they have been prediction. It is done on a routine basis. On the other benefited by fabrication/manufacturing related hand earthquakes are not something on which we contributions. In the recent years, development of have good early warning methods. sub-systems; optics related, or sub systems of electronics or even communication subsystems, earth As far as post disaster is concerned, it is essentially stations has taken place. In fact the setting up of the for mitigation measures, that means how do I make international ground stations has been one of the the effect of the disaster less when the next disaster major areas where industries have played a role. End- occurs. So what are the mitigation measures one to-end turn-key projects, they have been able to do. If needs to take, whether it is floods in terms of where you go beyond this field, they have also helped to put the embankments etc. So in fact in disasters we greatly in many of the satellite main frame structures, have three major things. One is pre disaster, during sensors, attitude sensors. Then there are large number disaster and post disaster. During disaster, it is of efforts in case of launch vehicles. useful for warning the people not only of the extent 6 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Industries are playing an extremely important role. Signatures: As President, ISRS, do you have any But, I would say to a large extent, it is still within the particular suggestions for reducing the timeline involved scientific organizations that we do many things in in the Government-Industry engagements, or are you India compared to the western world. For eg., if you satisfied with the current procedures in place? go and see outside, the entire payload itself is made RRN: You know one aspect perhaps relates to data by an industry, including design and development. policies. They have to do many of the things under In fact the space organizations restrict only to the supervision which perhaps takes a certain amount conceptualization, design, quality control, assurance, of time, which is perhaps hindering. If we have more testing and may be at some level of integration. In open data policy so it would certainly help. Recent RS India, it is not still true. Data Policy-2011 (See Page 179- Ed.) is a step in this direction. So, Indian industries have a large scope. Industries will survive only if they have necessary Second, we need not look at only satellite data as far infrastructure, and sustainability over a period of as remote sensing is concerned. There are a large no. time. That is likely to happen in future because now of activities which need to be done using aerial data Indian space programme has reached a certain level particularly, aerial stereo data, which are required for of maturity and there is going to be a sustainability of large scale urban planning infrastructure services in both communication, remote sensing, development related activities. All those things can including navigation. So that would result in having be taken by the industries and the time can be cut the industries to take up a greater role. I would say down provided we have more facilitating methods of that so far what industries have done is good, it will doing these things under the overall policy umbrellas. do much better in the years to come because of the sustained programmes. In addition to that, India is Signatures: Could you tell how ISRS is facilitating the also now in a position to provide its expertise and interaction among the Remote Sensing industry, services to other countries in the world. That itself government and other stakeholders in the RS domain? will give a greater scope for the industries. RRN: Right from the beginning ISRS has been promoting the industries by inviting them to our Our industries will be competitive in terms of the symposia and workshops, where they not only make availability of a large scientific and engineering presentations on their abilities but also they display manpower and our cost of manufacturing itself. So what they have to offer. That is one way in which we we should be able to take a larger fraction of the are promoting. We have also held commercial market that exists in the world in all aspects of the applications of remote sensing CARG symposia only space missions and their applications. for the industry etc. Third is we have also promoted industries by doing their certification process. This Signatures: Could you broadly categorise the domains in didn’t get completely concretized. But one of the which the industry contributes to the remote sensing suggestions was that the ISRS can take up and qualify activities in India, at present? which vendor is qualified to do a particular work. RRN: It is providing in (i) value added products & services. (ii) It is also engaged in development of Signatures: In your considered opinion, what does the software. (iii) Then in the area of data acquisition future hold for the industry contributions to RS activities? systems, international ground stations, etc.; (iv) in RRN: I think there is an enormous scope. There is an providing subsystems, the fabrication of electronics, increasing role as far as industries are concerned, mechanical assemblies, etc.; (v) then in some of the with the kind of growth that is expected in Remote communication subsystems. Sensing, GIS plus location based services.

7 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Signatures: What is your future vision for the Indian Society of Remote Sensing? Signatures: With respect to the industries, future RS RRN: My vision for the Indian Society of Remote symposia whether we can have one session for Sensing is that it should make an international industrialists? imprint in the field of remote sensing and that should RRN: Definitely, we can have one particular technical be the motto of the Indian society of remote sensing. session of innovations done by industry. May be we How can it do this? can call it Innovations Forum. Earlier, we were only Number one is the quality of research which is being giving them one session for presentations (more as an done not only in this country but also elsewhere advertisement). Instead of that, if they present what should be reflected in the papers, that we publish in innovations they have done, I think that would bring the journal of the Indian society of remote sensing. attention of the overall delegates to them. Right now, That is my first suggestion. So that when the standard not many people go and attend these particular of the journal or the quality of the papers which are sessions and we are also looking at them only published in the journal of ISRS is enhanced, it will perhaps as sponsors. I think that mind-set should bring a larger attention to the work that are being change. We should look at them as equal partners, in done. technology development, value added services etc. I think that should be reflected in the technical session. Second is that we should also play a very meaningful I think that would help. role in the international societies which are associated with RS; that is we become a major player in the Signatures: More industrialists should become part of the affairs of the International Society for Society. Photogrammetry and RS, may be in the International RRN: True. If you see IEEE and all similar societies Astronautical Congress related activities, also may be they have greater participation of industry in some other RS related Societies which do exist professionals. elsewhere, IEEE, etc. In addition to playing a major role in these international societies, we should also be Signatures: Dr. Navalgund, we the editorial team of very active in the Asian region. For eg., we have the Signatures and the office-bearers of Ahmedabad Chapter Asian Association of RS, AARS. There we at the thank you for sparing your time and sharing your views moment are not playing a very prominent role. So, with our readers. Do you have any other final comments or that is where, we should play a prominent role. remark? RRN: You know at present the Indian Society of Third is through the individuals. Individual members Remote Sensing which was established in 1969, is a 42 of the ISRS should make their mark, in positions of year adult. So it has reached its middle years or a international societies. And the fourth one I would matured state. ISRS is still considered largely of think that ISRS should bring out certain very special professionals who are engaged in the science and volumes, monographs which actually bring about the applications of remote sensing data. Whereas, I particular culture of the RS activities in India which would like to look at the ISRS, not just of the are driven by applications, success stories of RS in professionals who are in the science and applications actual applications in the society. If we do that, that but also of technologists, contributing greatly to the will bring home our society to the attention of growth of this society. international audience. Then I think the Indian society of remote sensing will become a major force to The second thing that I would also like to look at, is reckon with or a body who is respected in the that the ISRS should not be only a society of remote international arena. Not that, it is not there now, but it sensing, but should also be a society for will be much more than what it is. These are a few Photogrammetry and spatial sciences. I think it thoughts. should encompass or embody all aspects of the 8 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 technologies of GIS related things, then it should that we do, but also in managing the chapters’ become much more rounded not only in its activities, its financial resources etc. I think it should composition, but also in its professional content. I become the role model to all the chapters. think we should move towards that. Signatures: Thank you very much. We shall strive to do Signatures: Lastly, do you have any message to the that. members of Ahmedabad Chapter? RRN: Ahmedabad Chapter has always been a leading chapter of the ISRS right from the 1980s or so. Ahmedabad chapter should provide a lead in the conduct of the professional activities to other chapters of the society not only in the scientific programmes

ISRS Updates January-June 2011 ISRS Symposium, 2011 • ISRS Annual Convention and National Symposium, 2011 will be conducted during November 9-11, 2011 at Bhopal on the theme “Empowering Rural India through Space Technology”. • There are three pre-symposium tutorials on ‘Introduction to Open Source GIS’, ‘Satellite Navigational Applications” and “Crop Area Assessment: Mapping and Modeling” to be organized at Bhopal during November 06-07, 2011. • Details are available on website www.isrs2011bhopal.org. • There will be an ISPRS WG VIII/6 and VIII/8 International Workshop on “Earth Observation for Terrestrial Ecosystem” on November 08, 2011 at Bhopal. Details are available on website www.commission8.isprs.org/wg6/.

Other Important News • ISRS has become an ordinary member of Asian Association of Remote Sensing. ISRS plans to organize Asian Conference of Remote Sensing in near Future. • The Nominations for ISRS awards, 2011 are invited. The last date for nominations is September 30, 2011. • ISRS has launched its new website: http://www.isrsindia.in. • ISRS plans to bid for 2016 ISPRS Congress. For this a bidding team has been constituted. Dr. V. K. Dadhwal, Director, NRSC has been designated as Team Leader and Congress Director (nominated). ISRS Symposium, 2012 • ISRS Annual Convention and National Symposium, 2012 will be held in Delhi.

9 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Remote Sensing Applications - Software & Services Industry Contributions in International Remote Sensing Activities of Antrix Dr. Murthy Remilla Dy. Director, Business Development (Remote Sensing), Antrix Corporation Limited, ISRO HQ, Bangalore [email protected] “An Indian farmer standing in his field, opening hardware/ software developments, supply of his mobile, touching few tabs to know the components/sub-systems, fabrication/ test/ weather information and about the seeds before realization of parts for ground or onboard starting the sowing using precision farming; systems, data reception, data processing, another farmer, using web-based GIS on his applications on ground support/consultancy etc. mobile for locating the nearest market for selling his harvest or searching for the best market Indian Space Research Organisation (ISRO) is one price”. of the leading agencies in the field of spaceborne remote sensing with a host of communication and This may be an imaginary situation today but remote sensing satellites in the orbit serving may soon become a reality. Today, we are already different user needs. The Indian Space Agency, witnessing wonders in our daily life brought in ISRO has a rich heritage in space systems and by advances in technologies. The days have gone services and includes an impressive array of when people were finding difficulties in locating remote sensing satellites and their utilisation. addresses and directions. Today, web based India enjoys a leadership position in remote mapping/GIS services are becoming popular and sensing with the largest constellation of state of bringing convenience. No wonder, these art remote sensing satellites with versatile technology based services will be converging capabilities. Antrix Corporation Ltd., the further in the near future, with the launch and commercial and marketing arm of ISRO reaches spread of affordable tablet PCs. the services of ISRO and the Indian Space industry to the global customers. These details All these developments are made possible, more are given in the later section. with the active role of private industry and end users besides the advancement of technologies. 1. Satellite building/ launching: Traditionally, Though the advancements were happening research and development in space technologies, continuously in Information, Communication building/ launching of satellites has been the and space technologies for several decades; hallmark of only a few governments across the reaping their benefits and empowering the globe, like India, US, Japan, Europe, China. people has been a major contribution of the Today the commercial industry partners like industry through customised solutions and Digital Globe (USA), Geo Eye (USA), Imagesat services. International (Israel) and SaTRec (South Korea) When we look at the industry contribution to the are some of the fully commercial agencies remote sensing activities in general, we can make involved in developing and operating remote out that today industry is participating in 10 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 sensing satellites. Antrix Corporation Limited partners who receive, process and distribute IRS and Spot Image, though both are part of the imagery are in-turn enabling the growth of governmental systems are promoting remote industry chain locally for value addition and sensing activities on a commercial basis like advanced services. members of the industry. Antrix/ISRO have taken many industry ISRO transfers several technologies to the partners as stakeholders in building/realising industries and provides necessary training and International Ground Stations (IGS) for hand holding to the licencee with a guaranteed receiving IRS data. These industry partners buy back in majority of the cases. ISRO uses the contribute in the development of satellite services of several of these technology license specific hardware and other ground station holders and other industry partners in fabrication related hardware supply to Antrix for and supply of satellite hardware/subsystems in establishing these IGSs. structures, electronics, optics, power systems, reaction/control mechanisms etc., and also In the field of data processing, Antrix several software activities. Though the design is Corporation is liaisoned with the image by ISRO, the development, testing and system processing and Photogrammetric software level validation are actively carried out by industry for developing advanced products industry partners. from the IRS data. Specific examples in this area include the role of industry in processing stereo Similarly, Antrix has launched satellites of several images, digital elevation model and digital international customers on commercial basis surface/terrain modeling etc using Cartosat-1 using ISRO’s Polar Satellite Launch Vehicle stereo pairs. The industry contribution in this (PSLV). ISRO utilizes the services of several has been in enabling users of different COTS industry partners in the fabrication and supply of software packages for using IRS Cartosat-1 data subsystems for launch services as per the existing through six levels of stereo processing support. arrangements. Such an understanding with the industry has enabled IRS readiness of commercial packages 2. Satellite Data Reception and Processing: like LPS, ENVI, PCI. Many of the Indian Antrix Corporation has a network of 22 Geospatial industry players are successful not international ground stations spread across all the only in the Indian market but are making their continents receiving data from several IRS presence felt globally. satellites including Resourcesat-1, Cartosat-1, Cartosat-2 and Oceansat. Out of these 22, half of 3. Utilisation in Applications: Remote Sensing, the stations are owned, operated and managed by observation of objects and their features without private industry partners in those markets. Some coming into contact has the advantage of of the private industry partners include Euromap, providing synoptic, detailed information about Germany; Beijing Earth Observation, China; the land condition and land use etc., to the user EOTec, USA; ScanEx and Sovzond, Russia; community. For a long period, use of Remote Seaspace, USA who are making good business in Sensing has been confined to applications like the market segments and also bringing wider Natural Resources Management, Mapping or awareness and acceptance for IRS services. These Disaster Management mostly by governmental 11 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 agencies/decision makers. With the improvement decision support systems and project in the information content of the images use by implementation/ monitoring activities, Indian private and individuals is expanding in addition Space Research Organisation in collaboration to the core group of scientific and government with industry has developed an Integrated GIS users. Today, information revolution – the and Image Processing Software called IGiS. The combination of required information and its collaborator in this effort for ISRO’s Space timely delivery is made possible by the active role Applications Centre is an Ahmedabad based and involvement of private industry bringing the private company M/s. Scanpoint Geomatics benefits of the technological advancements to the Limited (SGL). The collaborator has been selected common man. The kind and level of information by ISRO for the development of IGiS after being provided is witnessing rapid change and considering many offers which include offers also the demands/expectations by the users is from MNCs. also ever increasing. The software consists of three key components

namely (i) IGiS Desktop software, an integrated Google Earth, Microsoft Virtual earth and other suite of advanced GIS and Image Processing services are some of the examples bringing tools, (ii) IGiS Geodata Server Gateway, an Spaceborne Remote Sensing Imageries to the interface for managing spatial data in a Relational desktops of common man. Bhuvan is a Geoportal Database management System(RDBMS) and (iii) of Indian Space Research Organisation IGiS Web Applications software, Internet-based Showcasing Indian Imaging Capabilities in Multi- GIS for distributing data and services using Map sensor, Multi-platform and Multi-temporal Browser. This package was specifically developed domain. This is a one stop versatile web based with the heritage of ISRO’s long experience in a Earth Observation visualization platform that variety of applications and also through a provides access to information valuable for carefully chosen industrial collaborative effort. engaging various developmental activities at the The software is also accompanied by advanced grass root level. modules including network analysis, terrain

analysis, 3D modeling and neural network While recognising the massive market of analysis. The IPR of the product lies jointly with agricultural sector in India and the potential use ISRO and Scanpoint whereas, Antrix is of remote sensing in agriculture as well as allied supporting the marketing of IGiS package. After services/ products, some software/consultancy an encouraging feedback from several user firms are coming with new ideas to launch segments in India, Antrix is planning an several service packages. These IT enabled international launch of this product for reaching services envision clubbing the advances in IT and the benefits of integrated and cost effective IP + communication with the benefits of Remote GiS suite to the global community. sensing technology to serve the range of stake holders in agricultural sector. Once this is Coupled with the advances in smart phones, successful, this may expand to other sectors Location Based Services (LBS) are gaining which are not traditional users of remote sensing. popularity and importance with several sectors of the economy embracing the new technologies. To Taking cognizance of the increasing role of meet this market potential, many industry Geographical Information System (GIS) in several players are coming up with innovative, user 12 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 friendly and cost effective packages/solutions ISRO to their applications on the ground and also that utilise the benefits of remote sensing in reaching the services of IRS to the Earth imagery, GIS and GPS. Observation community in the Global market.

4. International Marketing: In addition to the With the advances in the technology, increasing network of IGSs, Antrix has expanded its user demands and higher inclination from the presence and availability of IRS products and industry to join the remote sensing and other services to several national customers in the space based technology services, the future may international market through a wide network of witness increased level of industry participation 20 resellers. Needless to mention majority of them as well as expanded scope of activities in which are from the private industry hoisting the flag of the industry becomes an important stake holder. IRS in their market segments.

Thus, it can be concluded that several national and international industry partners are associates of Antrix Corporation in international remote sensing activities, right from satellite building for

Call for Articles

Readers are requested to contribute short articles for publication in the forthcoming issues in their own words, preferably as per the editorial calendar given on page-4, either as a brief survey of state of the art or as articles on specific work carried out by them, or as novel concepts related to the specific theme(s). The deadline for inclusion in the next issue on “Atmospheric & Oceanic Remote Sensing” is Sept 20, 2011. - Editorial Team

13 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Industry Participation in Remote Sensing A R Dasgupta Scanpoint Geomatics Ltd, Ahmedabad

Geospatial technologies in general and Remote In 2004, as remote sensing activities burgeoned the Sensing in particular are driven by industry, though then Chairman of ISRO, Dr. Madhavan Nair felt that this may not be apparent to most persons. While the the time was ripe to take another stab at indigenizing design and development of the sensors, the satellite image processing and GIS software because if the and the launcher and the ground segment are usage of IRS data was to be enhanced then it was spearheaded by ISRO, a government R&D institution, necessary that Indian users should have access to the material, components, subassemblies, tools, test image processing systems which were economically equipment, computers and software are all priced. ISRO had already developed and marketed its contributed by industry. This is not to downplay the IRS data processing software (DPS) globally through contribution of ISRO in designing and operating a the tie up of Antrix with EOSAT (later Space programme that is one of the most innovative and Imaging). Therefore it was felt that this expertise economical in the world but to highlight the fact that could be applied to the field of image processing as Industry is an unsung but very important partner in well. As it was Space Applications Centre which had this national effort. The story of the collaboration spearheaded the IRS DPS development it was between Scanpoint Geomatics Limited, Space decided to entrust SAC with this responsibility. Applications Centre, Indian Space Research SAC had earlier experience in joint development of Organisation and Antrix Corporation illustrates the software with industry when it took up the win-win solution that is possible when government, development of GIS software called ISROGIS under public sector and private sector come together. ISRO’s Technology Transfer programme. However,

this effort also had faced the problem of marketing As India entered the era of operational remote and after sales support and had failed. This time sensing through its Indian Remote Sensing Satellite around SAC decided on a model in which it would series in the 1980s, ISRO realized the importance of provide the specifications and the verification and image processing software for analysis of remotely validation support and leave the development to sensed data. However, image processing systems industry. A RFP was released and 13 industries, many were expensive those days. Therefore, ISRO set up well known MNCs included, were shortlisted after five Regional Remote Sensing Centres in different the initial screening. Finally, Scanpoint Geomatics Ltd parts of India equipped with the latest image was the company that could satisfy all the processing systems imported from France which requirements of the RFP and win the contract. could be made available to regional users in the states for a modest fee. Simultaneously, development of SGL worked very closely with SAC over the next five indigenous image processing software was revved up years and the beta version was tested by an ISRO and two systems, SIPS and ISROVISION, were wide team for one year before the software was developed jointly with Indian industry and placed in released formally on July 29, 2009 by Dr. Madhavan the market. Though cheaper by a huge margin the Nair, thus fulfilling his dream and desire. The marketing efforts of these systems floundered and by product, named IGiS v1.0, for Integrated GIS and IP the time IRS was into its third satellite, IRS-1C the Software, is a state of the art system incorporating all country was once again depending on imported the features required by projects being conducted by software. ISRO and its collaborators and also available in expensive imported software. SGL is assured 15 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 continuous support by ISRO and a proof of this Aperture Radar imagery analysis and a suite for support is that IGiS v1.1 could be released within 18 photogrammetry. For this again SGL is in discussion months of the release of the version 1.0. Version 1.1 with ISRO-SAC for the transfer of technology went through the same rigorous testing by an ISRO developed by them. In fact the suggestion to add SAR team and was released by Dr. R. R. Navalgund, imagery analysis came from Dr. Navalgund, Director, Director, SAC on January 27, 2011. SAC, illustrating the degree of support and goodwill that SAC-ISRO has for the product and the industry. Being sensitive to market needs, SGL is not satisfied by just selling boxes of software but prefers to take up In terms of marketing SGL has entered into an turn key projects and provide customised solutions to association with Antrix Corporation under which end users. Looking at the opportunities emerging Antrix and SGL work together to provide solutions to from the Restructured Accelerated Power customers. Under this association Antrix is now a Development and Reforms Programme, R-APDRP, registered GIS Solution Provider under the R-APDRP SGL has added the Power Line Package PLP to IGiS. programme with SGL providing the technical back Similarly, seizing the opportunity provided by the office support. National Land Records Modernisation Programme, In conclusion, the story of SGL and IGiS illustrates NLRMP, SGL has developed a Land Records how private industry, public sector and government Information Management System, LRIMS. Apart from R&D laboratories can work together to produce and these, there are customisations of IGiS for market world class products at very economical applications in mining, urban planning and defence. prices. Further, Indian industry is much better placed IGiS is the only Indian software that has been to service Indian users by providing total solutions as certified by the Open Geospatial Consortium as opposed to shrink wrapped boxes marketed by sales compliant with its specifications for Web Map representatives of MNC suppliers. ISRO has done a Services and Web Coverage Services. significant service to Indian users of remotely sensed Keeping in mind the current trends and the need to data by providing IRS satellites and software like IGiS support ISRO’s future IRS satellites, plans are to analyse this data. Scanpoint Geomatics is proud to underway to add advanced modules for Synthetic be a partner in this effort with ISRO and Antrix.

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16 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Increasing Role of Private Industry in RS Activities Jiping Li General Manager, Beijing Earth Observation Inc. In recent years, the remote sensing industry has (better than 2.5 m) and along track stereo imaging become more and more prosperous in China market capability for cartographic applications. thanks to the growth of demand and the high speed development of economy. Beijing Eastdawn Secondly, Apart from the stereo mode, the satellite is Information technology Co., Ltd. (EDIT) is an also equipped to operate in the wide swath mode. international geospatial data production and remote When operated in this mode the satellite can be sensing company, with headquarters in Beijing, maneuvered such that image strips will fall side by China. EDIT has a Data Production Center, with a side so that wider swath images of 55 km are obtained capacity of more than one thousand and a half by the cameras. operators and managers. EDIT is one of the largest privately owned geospatial data production Thirdly, the precision of elevation/plane imaging is companies in China. very high, due to the fixed B/H ratio of 0.62 of stereo pairs and the across track resolution of 2.187 m (at Remote sensing business which is the main part of Nadir) of the Aft camera. So the derived DEM can EDIT has a big growth in these years. EDIT is the meet the demand of scale 1:25000, while the single exclusive distributor of CartoSat-1(IRS-P5) imagery image can meet the updating task demand of and RapidEye imagery, the master distributor of topographic maps of scale 1:10000. IKONOS, GeoEye-1 imagery, and has a sole marketing agreement for COSMO-SkyMed imagery Fourthly, the platform can be tilted up to ± 23 degrees for the entire China market. Among all of these 12 in the across track direction, thereby providing a short optical and radar satellites, CartoSat-1 is the first data revisit period of 5 days, which can meet the special that EDIT distributes in China market, and up to now needs of an urgent task. it is also the only one that EDIT receives the data by its own ground segment. The receiving of CartoSat-1 CartoSat-1 is widely used in areas of cartographic data in China by EDIT started from 2006, distributed applications, urban management, disaster assessment, to domestic customers, which provides a solid relief planning and management, environmental support for the remote sensing business of EDIT. assessment and other GIS applications. Here after are CartoSat-1 helps to cultivate many important clients some examples. EDIT also releases value added and ignites the prosperity of remote sensing business products and services, such as Image Earth 2011, of EDIT. CartoSat-1 is an advanced 3-axis body which is true color DOM product merged with stabilized remote sensing satellite, which was put into CartoSat-1 and other multi-spectral bands of other 618 km Sun synchronous orbit on May 05, 2005. It has available sensors. Image Earth 2011 is 2.5 m spatial many advantages comparing to other satellites of its resolution and gives a seamless cover over whole era. China. It has a capacity of updating 5,000,000 sq km area annually. It can meet the plug-and-play data Firstly, CartoSat-1 has two panchromatic cameras demand of GIS users. Due to the moderate resolution, mounted with a tilt of +26 degrees (Fore) and -5 pointing accuracy, data quantity and reasonable price, degrees (Aft) from yaw axis in Yaw-Roll plane, which it has become ideal base map for large GIS systems of can provide data with enhanced spatial resolution many industries.

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Fig. 1 Beijing Capital International Airport, DOM product merged by IRS-P5 and IRS-P6

Fig. 2 Beijing Olympic venues, DLG product of IRS-P5 Telecom base Telecom base station

Fig. 3 Constructing digital 3D community, building height extracted from stereo pairs of IRS-P5 Fig. 4 Building heights extracted from stereo pairs of IRS-P5, for the locations selection of telecom base stations

19 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 GIS and Remote Sensing Applications Related Services from CompuSense Automation

Established in 1997, CompuSense Automation is about 50 land use mapping projects for Environment Ahmedabad based, GIS and Remote Sensing Impact Assessment Studies. For different industries Applications service provider company. Apart from like chemical, pharmaceutical, cement, ports, providing services to ISRO, for their important and infrastructure and mining. Specific remote sensing national level projects like NR Census, Coastal Zone studies like mangrove mapping and monitoring, Information System, Glacier Inventory, Glacier Mass studying impact of water conversion activities, Balance, Snow Cover mapping, Lunar DEM etc. assessment of cultivable land for bio mass based CompuSense Automation has been involved in Urban power project and change analysis studies are some of Planning projects of Government of Orissa, for the areas in which CompuSense Automation has Preparation of Comprehensive Development Plan of provided its services. Sambalpur region. Company has also undertaken

Using Commercial Software to Enhance Commercial Imaging Acquisition Adam Gorski, Analytical Graphics, Inc., Exton, PA USA, [email protected]

Abstract – This paper documents the ways 1. Commercial Remote Sensing Challenge – Everyone commercially available software from Analytical can benefit from remote sensing. As anyone who has Graphics, Inc. (AGI) can improve the acquisition of used Google Earth, Bing Maps or Bhuvan can attest, remote sensing products by reducing the time and seeing the Earth in high resolution from above cost required to procure new imagery from remote provides a unique perspective that empowers sensing satellites. The method uses the industry- decision-making and planning on scales never seen standard STK desktop software and software before in human history. However, getting new development kits and the new Standard Object imagery is a complex job. Satellite tasking (or Catalog (SOC) library of satellite platforms and requesting a satellite operator to take an image of a sensor models. AGI’s STK and the STK Engine specific place) is a costly and time-consuming software development kit are commercial software endeavor. Tasking for some satellites is free, while packages with more than 22 years of history in the other satellites cost $10,000 or more per image remote sensing market. The SOC is a new effort from request. Furthermore, it may take days or weeks for a AGI to create a community-driven library of single satellite to pass over a target in such a way that spacecraft with accurate and thorough descriptions its sensors can retrieve an image of a specific area of mission capabilities. SOC entries can be searched (assuming there is no cloud cover during that pass). and the data automatically loaded into STK for For response to flooding, fires, storms or other simulation and planning. disasters, this duration is often not acceptable. However, with commercial software tools outlined

20 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 below, that process can be greatly improved by data can be procured publicly. Fig. 1 shows the providing knowledge and choice to individuals. growth of this market along with the distribution of countries contributing to it. With so many publicly 2. Commercial Remote Sensing Industry – The available sources of data, resolutions varying from satellite remote sensing industry has seen a dramatic tens of meters to less than 1 meter; satellites with change in the past 20 years. In 1991, there were only different agility (the ability to change orientation and five nations that had access to satellite remote point at a target); sensors with different swaths (the sensing assets: the United States, Japan, Russia, India area on the Earth’s surface it can cover); payloads and France.[1] Since then, the world has seen the with different operating frequencies and satellite impact of low-cost and micro-satellite technology orbits with different revisit rates, it becomes spread around the world with a current fleet of 62 challenging for someone who is not a rocket scientist satellites with optical payloads from more than 19 to know which satellite is really best for getting an countries. [2] image quickly and affordably. Fig. 2 shows this Forty-seven of these platforms are challenging problem in STK’s 3D environment civilian/commercial programs, and most of their populated with the active imaging satellites.

Fig. 1: Number and distribution of commercial remote sensing satellites [1] 4. Software modeling of remote sensing platforms – orbits (such as the times when they will fly over a Fortunately for the global remote sensing certain point on the globe). STK also includes an community, AGI has been producing software with interface to the United States Strategic Command the ability to answer these difficult questions for the (USSTRATCOM) database of satellite orbits using past 22 years. STK is a robust and highly accurate Two-Line Element (TLE) sets that allows the software simulation software that predicts the location of to predict the locations of actual satellites in orbit. satellites and performs time-based analysis on their Additionally, STK includes the capability to model 21 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 the sensor characteristics of satellite payloads and AGI’s data management and collaboration software analyze their line of sight to targets on the ground. package. The ADF stores, manages and disseminates remote sensing assets in much the same way as a Recently, AGI embarked on a new initiative to make geographic information system (GIS) collects, stores searching for this information easier for our and disseminates geography. community of 40,000 users. The company created a service called the Standard Object Catalog (SOC) that Together, STK and the SOC allow users to search for contains a library of accurate and thorough any set of active remote sensing satellites and descriptions of satellite payloads. [3] The SOC also accurately predict the times when any of these contains STK-formatted objects for use in image satellites’ sensors will be able to acquire an image in collection planning and other analysis tasks. The SOC question. data is available from a web portal at http://soc.agi.com as well as built in to the STK software through the AGI Data Federate (ADF),

Fig. 2: Screenshot from STK 3D environment using SOC satellite orbit and sensor data

22 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

Fig. 3: STK equations for modeling sensor resolution from STK desktop interactive help documentation

5. Remote sensing for the GIS customer – The and security. To best serve these industries, remote integration of GIS into remote sensing systems is sensing systems need to tie directly into the critical to meeting modern technological authoritative content of GIS systems. AGI software requirements, in that GIS is used by many industries meets that requirement by interoperating directly including transportation, the environment, commerce with GIS through modern

Fig. 4: Satellite Overflight Portal, an AGI implementation of web-based satellite imagery planning system built with AGI software development kits and SOC sensor data 23 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 geospatial standards. The features housed within the target location and set of criteria (date, image GIS can be used as input parameters to the remote direction, image elevation, etc), and the software will sensing system, and the features’ geography and return a time-based list of satellites that meet those associated attributes can optimize collection and criteria. overall performance of the system. 7. Conclusion – The satellite remote sensing industry 6. Benefits of remote sensing prediction – With the has become a complex and challenging market to combination of AGI’s commercial STK software and enter for those who are not already experts in the the content of the SOC, anyone can now determine field. However, recent advances in software which satellites will cover a target in the shortest technology and data distribution allow anyone with amount of time and allows users to go to the right the right set of tools to face this challenge easily and imagery provider for their request. Additionally, quickly. AGI’s commercial software and SOC data users can look back at historical satellite orbits to see library are examples of such software/data which providers could have taken a particular image combinations that empower users to save time, under particular conditions such as lighting, weather money and effort in the acquisition of remote sensing and image direction. products.

The true benefits of these capabilities are realized References when a user combines the analytical power of STK [1] Stoney, William E., “Markets and software with weather data, large lists of targets and Opportunities?” Earth Imaging Journal, September robust scheduling algorithms to optimize the 2009. http:// www.eijournal.com/ collection of assets based on resolution, priority and Markets_Opportunities.asp cost. [2] AGI Standard Object Catalog April 2011. http://soc.agi.com Moreover, AGI has used our software development [3] Kaslow, David, “COTS Implementation of a kits to showcase the flexible nature of these Sensor Planning Service GetFeasibility Operation capabilities in an online showcase: - Interim Status #2”, 2011 IEEE Aerospace http://spacedata.agi.com. From the Satellite Applications Conference Proceedings, March 5- Overflight Portal, you can select a list of satellites, a 12, 2011.

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24 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Services and Innovative Technology Development Globaltech India, Ahmedabad

1. Introduction: Globaltech is providing Outsourcing that while doing development work, we need services to Space Applications Centre (SAC) for to develop new circuits boards (Hardware) for Electronics Engineers and Software engineers since different trials. In this process we were August 2010. At present we have 48 Engineers are spending lots of time, Money and resources in working at SAC in different divisions. We also development for hardware & testing of its provide similar Technical services to our clients in software... Canada, Israel, Belgium, Germany, United Kingdom, • We thought of developing one Platform where Italy, Taiwan etc. for development of their products. different programming Technology : VLSI , Real-time Operating system , and Embedded , GlobalTech expertise in Software solutions for can be done Seamless , eliminating business Application, Embedded solutions, FPGA & requirement of new board , and also testing ASIC designs and Network/security solutions , can be done using various interfaces, so that it having 900 + man years of experience since 1999 . becomes Multipurpose system, where All sort of Development can be taken care off. Globaltech offer services to Global customers • Our ProSys is the result of this thought, and it through Global Business partners , to Israel , Europe , is completely in house designed by Taiwan , USA , Brazil , Canada etc. GlobalTech GlobalTech Investing almost 200 Man months. always ahead in technology by partnering with world leader in technology like Microsoft, Intel, Mentor Graphics, Microchip , Texas .

In last one decade of our existence, we have delivered more than 100 projects in different domain, on different technologies globally.

We started development of our product for multitasking. Multiprocessing platform for complex controlling. so we came out with Prosys1000. It is Platform where FPGA, 32 bit controller and 8 bit ProSys: Salient Features controllers are interconnected. • Powerful Million Gate Xilinx Spartan FPGA , Concurrent Processing ProSys1000: 1st of its kind having three different • 32-Bits and 8-Bits PIC Microcontroller for programming technologies on one platform with built RTOS and Embedded. in soft components. • Onboard Memory. • This year PROSYS had been awarded by • Multiple 16-Bits ADCs and DACs for GESIA for best Innovation in ICT Industry. Analogue peripherals • This has been selected by CBI, Nederland • 80 Multipurpose Input/output Ports on Government to promote to Europe for next boards, Expandable upto Over 400 ports for five years. Sensors and actuators, motors etc. • This product reduce Time to Market for OEM • Interfaced to 5.7” LCD TFT Touch Panel for in complex controlling field , as we observed HMI.

25 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 • Industry standard peripherals such as USB, (2) Wireless communication Ethernet and UART for connectivity with (3) Data acquisition local/Remote PC (4) Educational Institute • JTAG and PIC Kit programmer to program (5) Robotics OEM FPGA and Microcontroller Compact size ProSys: Application: (1) Industrial Control.

HISTORICAL REMOTE SENSING 1. The glass was discovered by the phoenicinas around 3500 BC while cooking on sand.

The first lens was shaped from the glass after 5000 years, which led to the invention of a simple telescope by Hans Lippershey of Holland. The first astronomical telescope

was invented by scientist Galileo Galilei of Italy.

2. In 1704, Sir Issac Newton gave new concept in telescope design whereby instead of glass lenses, a curved mirror was used to gather in light and reflect it back to a point of focus. This reflector telescope had opened the door to magnifying objects millions of times--far beyond what could ever be obtained with a lens. 3. A binocular is an optical instrument for providing a magnified view of distant objects, consisting of two similar telescopes, one for each eye, mounted on a single frame. The first binocular telescope was invented by J. P. Lemiere in 1825. 4. Winds provide information about the weather and aid in its forecasting. In 1450, the Italian art architect Leon Battista Alberti invented the first mechanical anemometer. This instrument consisted of a disk placed perpendicular to the wind. It would rotate by the force of the wind, and by the angle of inclination of the disk the wind force momentary showed itself. 5. Historically, the first photos were taken from a small rocket designed by Alfred Nobel, at a height of about 100 meters, and launched in 1897 over a Swedish landscape. 6. On October 24, 1946, the V-2 series U.S. launcher which housed a motion picture camera in its nose cone acquired a series of views of the Earth's surface as it proceeded to a 134 km (83 miles) altitude. Compiled by: Amit Shukla

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27 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 An Interview with Shri MV Appa Rao, Managing Director, Centum Electronics Limited

Signatures: Shri. Appa Rao, satellite bus systems related hardware delivered by at the outset, ISRS-AC is Centum comprise of dc-dc converters, EMI filters, thankful to you for sparing reaction wheel controllers, Earth and Sun sensors, your time for this Interview. relay drivers, signal conditioners and multiplexers. Could you tell us briefly about Centum’s achievements in launch vehicle M/s. CENTUM Group of applications are in the area of Inertial Navigation companies and nature of its subsystems, accleration sensor data processing and activities? 1553 interface units. Some of the products find dual AR: Thank you so much for application in launch vehicle and satellite bus giving the opportunity to systems. We are proud to be associated with share our views. Centum started its operation in 1994- Chandrayaan-1, where we had several modules in 95. Today, we have three distinct business units (BUs). Inertial Navigation area performing extremely well Strategic Electronics BU is involved in Design, during transition from Earth orbit to the moon orbit. Development, Manufacturing and delivery of In the defense segment, Centum has products like qualified Hi-reliability Electronics hardware such as Missile Interface Units, Onboard computers, power EPCs, Sensors and Sensor Electronics, Data supplies, BLDC controllers in missile & torpedo Acquisition Units, BLDC Controllers, Missile Interface electronics. Centum also builds Flight Data Recorders Units, Onboard Computers for Space, Defense and (the black box of an Aeroplane). About 70% of Aerospace applications. Electronics Manufacturing Centum group’s business comes from turn-key Services BU manufactures Build to Print – BTP contracts. Most of our business with ISRO is also on products such as STM4, STM16 units, flame analysers, turnkey basis. We have a strong design team that Gas chromatography products, Metering and Meter understands the quality requirements of components Interface units for Industrial, Medical and Telecom and materials. Ability to have a strong supply chain markets. The Frequency Controlled Products BU management with vendors from all parts of the Designs and Manufactures Crystals and Crystal globe, Incoming Goods Inspection procedures, oscillators mainly, for Telecom, Defense and Space manufacturing, testing and reliability screening are markets and is one of the top three OCXO key to successful execution of turnkey projects. One manufacturing company in the world. As a group, we also has to be financially and commercially strong to are more than 1000 professionals located in Bangalore be able to buy materials with Government and and our Sales offices/Sales partners are located in Statutory compliances in place. Europe and USA. Signatures: CENTUM had worked on many projects and Signatures: M/s. CENTUM has created a niche space for programmes of ISRO. Kindly let us know about its itself as a leading industry in India’s Aerospace sector. contributions in the field of subsystem delivery, electronic Will you share with us some of your major achievements? fabrication and qualification and subsystem development AR: Starting in a small way about ten years ago in for ISRO’s programmes. aerospace sector, today we have some major AR: Centum has a strong Design and Engineering achievements that we can proudly talk about. Some team which has been associated with various ISRO of these are the modules and subsystems in Payload centres in Designing and Developing products for Electronics like Met Payload modules, power Space in three distinct levels viz., Subsystems, supplies for RF subsystems in C and Ku bands, Modules and Niche Components (like Microcircuits Power processing units and Tile Control EPCs. The and Oscillators). ISRO is one of the key customers for

28 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 our Strategic Electronics Business Unit and hence, we as well. Reference sample given by SAC had a also serve ISRO with Fabrication and Screening volume of approximately 100 cubic mm and weight activities in ‘Build to Print - BTP’ mode. of about 700 gms. The challenge that was given to us We have designed and developed and delivered by SAC was to reduce the weight and volume by Power Conditioning and Processing Units (PCPU), 50%. Centum used various technologies such as thick Tile Control Unit EPCs and TR Controllers for film technology, planar magnetics (first time for RISAT-1, Customized multi-output EPCs for Ku- and ISRO), SMT technology and also used materials like C-band payloads for GSAT missions, Power Supply Magnesium alloy to meet the challenge given. Each trays for Met payload in INSAT-3D, Custom built of these technologies had to go through rigorous EPCs for IRNSS satellites, Standard dc-dc hybrid qualification process and at the end, we were able to microcircuits for housekeeping systems, Data meet the requirements. This can be an excellent case Acquisition Units for launch vehicles, Reaction wheel study on how ISRO and private industry can work controllers and SADA potentiometers for satellites. together to develop new technologies and deliver the space grade products for Indian space programmes. Signatures: CENTUM has contributed significantly in Also, unlike most of the space hardware, where the development of space grade Power Supply modules for quantities are mostly in single or at best double digit, ISRO’s Remote Sensing, Communication & Navigation in this case we had to deliver more than 350 payloads and satellites. Will you throw some light on your subsystems which itself was a challenge. Going major accomplishments in this segment? through the regular design and QA reviews, ramping AR: Centum is extremely proud to be associated with up the production to a steady state supply of ~35 per all the programmes of ISRO and have already month necessitated thorough planning, co-ordination delivered qualified Flight EPCs customized for with SAC. At each of the crucial stages, SAC team Remote sensing, communications and Navigational provided considerable guidance and support. payloads and Satellites. The recent deliveries for IRNSS and GSAT series of satellites comprised Signatures: Why are only very few private industry design to FM delivery of many types of EPCs and in players involved in building space qualified subsystems in substantial quantities. Recently, for INSAT-3D Met India? payload, due to a risk mitigation strategy of ISRO, we AR: Space business cannot be everybody’s cup of tea. were asked to design, develop, qualify and deliver It needs lot of patience and tenacity to be in this power supply trays within a time span of six months. business. The reasons why you see limited private The on time deliveries, in my mind was due to a industry players in space business in India are: (1) It great team effort between Centum and SAC, as is very high-tech (It is rocket science! Ha..ha..) developing these high end products in such a short business which needs highly qualified technical period is extremely difficult and rare. Apart from experts (2) Huge investments are required in this, we also deliver standard DC-DC Converters to infrastructure for production and reliability testing of ISRO. the product. Quantities required may not justify the investments and hence Private industry has a challenge. (3) The approval cycles to be space Signatures: What were the challenges involved in the qualified take many years without a return, which realization and delivery of Power Conditioning and discourages the private industries. (4) Continuous Processing Unit (PCPU) for ISRO’s RISAT-1 Synthetic investments are required in R&D in developing the Aperture Radar (SAR) Payload? new technologies and products (5) Government of AR: This particular program was the first single India’s procurement policy of not having long term largest program for Centum in the space arena and I contracts with private industry makes it difficult to also think, one of the large programs for SAC/ISRO

29 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 invest, not knowing whether the business continuity team members actively participating and asking will be there or not. highly technical questions. We are able to design and Inspite of all these constraints, we are definitely manufacture many complex and technically seeing a lot more private industry participation in challenging subsystems for SAC/ISRO, thanks to Indian Space programme and I am sure this will their constant encouragement and technical increase with increased outlay of ISRO’s budget. guidance. This gesture of SAC helped Centum to take up low volume, long gestation products/projects for Signatures: You have been responsible for bringing ISRO. CENTUM to its current status as industry leader in aerospace sector. What was your motivation and Signatures: What types of Infrastructure and R&D set- inspiration in developing such advanced fabrication and ups exist at CENTUM? Are there any plans for testing facilities? Will you share some of your experiences diversification and augmentation? during this long journey? AR: I think our infrastructure and R&D can be easily AR: At Centum, our vision has always been to create compared with any of the space suppliers in Europe value by contributing to the success of our customers and USA. We have been continuously augmenting and by providing the best-in-class Electronic Design the infrastructure and keep adding new machines to and Manufacturing solutions. We have always address new process requirements. This year we looked for opportunities in high technology have set up a class 1K clean room to enhance our segments. As a company, once we decide to be in a capabilities. Last year we established a brand new particular product or a sector, we thrive to be world oscillator factory that will also address the space class. To achieve this, we have no choice but to requirements. Today, we have almost everything that continuously invest in our people and infrastructure. world’s best EPC, Modules and Subsystem suppliers Being in Bangalore has certainly been an advantage have, with technologies ranging from thick and thin and our initial association and success with ISAC has film, quartz crystal processing, high end oscillators also helped. and SMT/Mixed PCBA besides qualified and motivated techno-managerial team. Signatures: SAC/ISRO has been credited with putting We are also evaluating other products and untiring efforts and encouraging the indigenous Indian technologies that we would like to enter, but I cannot industries and industry participation in Indian Space elaborate at this point. programme. Kindly share CENTUM’s experience with

SAC/ISRO on this. Signatures: Where does CENTUM stand today in terms AR: ISRO has always treated its suppliers as of technology capabilities in the International competitive ‘Partners’ in true sense of the word. Centum is a very scenario? In what way the association with ISRO enabled strong case study for this. Centum started as only a CENTUM to compete in the International market? hybrid supplier to ISRO and SAC/ISRO encouraged AR: We are currently being viewed by some of the us to take up the development of more complex European space customers as a serious potential products. SAC team provided helping hand to supplier for them. We are in advanced stages of Centum in achieving better results. SAC also shared negotiations for some of their projects. Association their vast experience in procurement of components with ISRO enabled Centum to develop right to establishment of complex test facility like thermo- technologies and products and helped us have space vacuum chamber. My team tells me that SAC and heritage. The experience of the team working in ISRO team’s design and technical reviews are an Strategic Electronics business unit in following space excellent learning platforms for Centum Engineers standards for workmanship and quality management and Managers. It gives both width and depth since systems definitely played a dominant role in Centum the reviews are always done with cross functional competing in the International market. 30 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 country and highlight the gaps required to be Signatures: What role can professional societies like ISRS addressed when it comes to establishing the play for increased industry participation in government capabilities and capacities. ISRS can play the role of a bodies like ISRO, DRDO etc.? Do you have any catalyst in Industry bridging the gaps to reach self suggestions? reliance in Space and Defense systems and also for AR: Societies like ISRS can play a very crucial role in India to become a leader in International space bringing the Indian Industry participation in a scenerio. ISRS can also help Industries to address mission-critical projects for Indian Space and Defense some of their commercial issues that are making the sectors. ISRS having members with vast technical private Industry participation in Indian Space, experience in various technology fields, can arrange Defense and Aerospace difficult, by representing the seminars and workshops on the latest trends in the Industries point of view with the Government, ISRO technology for realizing some of their complex and the DRDO labs. missions. They can focus on India’s standing as a

A Brief Profile of Shri Appa Rao Mallavarapu Shri Appa Rao Mallavarapu received his Master’s degree from Dalhousie University in Canada and Bachelor’s degree from Bangalore University. He is also a Ford foundation scholar. Shri Appa Rao is the founder and Managing Director of Centum Electronics Limited, which designs and manufactures Hi-tech electronic subsystems, modules and components. Centum has received many quality and export awards from customers, industry bodies and the Government including the Platinum award for excellence in manufacturing from Frost & Sullivan.

NATURAL REMOTE SENSING 1. The cloud toads are able to detect environmental changes missed by people - such as the release of gases or charged particles from the ground, before seismic events. Thus, they reach the safe places much ahead of actual struck of the earthquake. 2. The shark can smell a drop of blood diluted in 100 liters of water and coral fish also have a smell memory of the reef where they came from. 3. Lions often hunt at night because their eyes can see about seven times better in the dark than humans. 4. When the humidity starts to build, millions of Earth-bound ants seem to miraculously sprout wings and take to the skies. Ants grow wings just before the first rain storm of summer. 5. Birds are able to hear low frequency sounds bouncing off mountains. 6. Desert ants have evolved special eyes that detect skylight polarization, which they then use to find their way around their sandy habitat. Compiled by: Amit Shukla

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32 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Remote Sensing Payload Hardware: Electro-Optical Sensors

Multispectral and Hyperspectral Sensors for Remote Sensing Sukbhir Kullar, James Miller, Andrey Lomako, Nixon O Teledyne DALSA Inc, 605 McMurray Road, Waterloo, Ontario, Canada, N2V 2E9

Introduction: Teledyne DALSA has developed to 16k pixels. Higher resolutions featuring pixel sizes Multispectral and Hyperspectral sensors using as small as 2.5 microns are envisioned in the near advanced Charge Coupled Device (CCD) fabrication future1, 2, 3. Most of these Multispectral sensors are processes combined with high performance dichroic based upon TDI CCDs but sensors with Line scan filters. These sensors have been designed to be CCDs have also been developed. In the case of TDI radiation hard and to be able to withstand harsh CCD-based sensors the number of TDI stages is environmental conditions typical of remote sensing selectable between 2 to 64 for B zones and 4 to 128 for applications. Multispectral devices contain multiple P zone. The key requirements for these sensors are imaging zones within a single silicon chip. These high dynamic range, tolerance to ionizing radiation spectral zones are sensitive to different wavelength and a small overall package size. Dynamic ranges as regions. Advanced dichroic filters are bonded onto high as 8000:1 have been achieved. Noise levels of as the cover glass directly in the imaging path of these low as 32e- have been achieved at 25MHz readout spectral zones. Teledyne DALSA’s Hyperspectral speeds. Radiation tolerance has been proven up to sensors are typically developed with split frame doses as high as 80 krad(Si) (Gamma ray). The transfer CCD architecture using back side thinning spacing between adjacent zones is of the order of technology that provides very high quantum millimeters. Fig. 2 shows a schematic of the CCD efficiencies (QE) over a wide wavelength range. architecture for a Multispectral sensor. Teledyne DALSA’s Multispectral and Hyperspectral Dichroic Filters: The Multispectral filters used for technologies are capable of producing sensors with these devices are multi-layered thin film dielectric dimensions as large as six inch diameter silicon interference coatings that enable very high wafers. transmittance and bandwidth selectivity. Measured Mutispectral Sensors: Teledyne DALSA has results for a 5-band filter are presented in Fig. 3. We developed a unique process combining patterned typically achieve in-band average transmitances of Multispectral filter technology with multi-segmented >90% and out-of-band average transmitances of <1%. line scan / Time Delay and Integration (TDI) CCD Further suppression of out-of-band transmittance is technology within a single package to realize a achievable with increased number of coating layers. compact Multispectral sensor. Fig. 1 shows a fully These filters are precisely aligned to the imaging assembled Multispectral device and device cross- zones of the CCD. The dichroic filters are deposited section showing dichroic filters and CCD. on a single glass substrate and involve a few CCD: The CCD design of Multispectral sensors hundred coating depositions to get the required high developed by Teledyne DALSA includes a high performance. The filters are patterned using a resolution Panchromatic (P) zone with pixel sizes in lithographic process. A black coating with low the range of 7 to 13 microns, and four (or more) reflectance and low transmittance is deposited Multispectral (B) zones with relatively lower between adjacent colour filter coatings. Completed resolution (depending upon the ratio of pixel sizes filters are tested for robustness to environmental between B and P zones). The exact resolution is kept factors such as humidity, temperature, ionizing confidential for proprietary reasons. However, radiation and overall mechanical strength typical resolutions for this application range from 4k

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Fig. 1: Five Band Multispectral Sensor (Left - fully assembled device; Right - device cross-section).

Fig.2: CCD Architecture Fig. 3: Measured Filter Spectral Response

Hyperspectral Sensors: Hyperspectral sensors devices approaches 80dB due to low read noise and designed at Teledyne DALSA offer high QE, high high full well capacity. frame rates and low smear. To achieve high QE these Typical QE performance of Teledyne DALSA back sensors use back side thinning technology. side illuminated (BSI) sensors is shown in Fig. 5. The Hyperspectral sensors are typically based on frame need of Hyperspectral sensors for high QE typically transfer or split-frame transfer CCD architectures. A translates into the need for BSI, which requires special typical split-frame transfer sensor architecture is fabrication and packaging. These sensors are also shown in Fig. 4. The frame transfer architecture designed to be radiation hard. The sensors are housed allows for a shuttering functionality to be in ruggedized packages with high reliability capable implemented in the device. The shutter efficiency is of withstanding the harsh environmental conditions also related to the exposure time in comparison to the typical in the space environment. time it takes to shift the image into the storage region. Conclusion: Teledyne DALSA has developed high Teledyne DALSA’s expertise in designing sensors performance Multispectral and Hyperspectral sensors with short vertical transfer times (<250ns) helps in for remote sensing applications. Multispectral sensors reducing smear to low levels. Typically we achieve a are produced by efficiently combining CCDs with smear performance less than 1% even at frame rates as dichroic filter arrays. These sensors are compact and high as 300Hz. Other important considerations for highly reliable. Teledyne DALSA’s back side thinning these devices are anti-blooming, low noise readout, process allows development of Hyperspectral sensors and multi-tapped output architectures. Multi-tap with very high QE, high frame rates, low noise and architectures allow for high speed readout and high dynamic range. These sensors have been consequently high frame rates (>300Hz) as well as designed to be radiation hard and to be able to allowing for slower clock readout circuits per tap with withstand harsh environmental conditions typical of resulting lower noise. The dynamic range for these remote sensing applications.

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Fig. 4: Hyperspectral CCD Architecture Fig. 5: Typical QE of a Hyperspectral BSI Sensor

References: L. Wu, N. O, C. Draijer, J. Bosiers, H. van Kuijk and H. Stoldt, “Stitched mk x 96 7µm Pixel TDI [1] Brian Benwell, Nixon O, Gary Allan, Jonathan Sensor”, CCD & AIS Workshop, Karuizawa, Huras, Melanie Ledgerwood, “12k 5 μm linescan 2005. CCD sensor with 320 MHz data rate”, Presented at the IEEE Workshop on Charge Coupled [2] Nixon O, Lei Wu, Melanie Ledgerwood, John Devices and Advanced Image Sensors, 2005. Nam, Jonathan Huras, “2.5 µm Pixel Linear CCD”, Presented at the International Image Sensors Workshop, May 2007.

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37 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Hyperspectral CMOS Imager P.A.Jerram1, M.Fryer1, J.Pratlong1, A.Pike1, A.Walker1, B.Dierickx2, B.Dupont2, A.Defernez2 1e2v technologies ltd, 106 Waterhouse Lane, Chelmsford, CM1 2QU, UK. 2Caeleste CVBA, Generaal Capiaumontstraat 11, 2600 Antwerp Belgium

1. Introduction: CCDs have been used for many years Fig. 1. The satellite scans the ground with the for hyperspectral imaging missions and have been spectrum from a narrow strip being split across the extremely successful. These include the Medium imager. The row data from the device then provides Resolution Imaging Spectrometer (MERIS) on spatial information and the column data provides Envisat, the Compact High Resolution Imaging spectral information. Wavelengths of interest Spectrometer (CHRIS) on Proba and the Ozone generally range from the ultra-violet to near infra-red. Monitoring Instrument operating in the UV spectral Hyperspectral imaging differs from multispectral region. ESA is also planning a number of further imaging in that the entire spectrum is distributed missions that are likely to use CCD technology across the device and may be divided into bands as (Sentinel 3, 4 and 5). However CMOS sensors have a required, whereas in multispectral imaging discrete number of advantages which means that they will spectral bands are viewed using separate linear probably be used for hyperspectral applications in the arrays. longer term.

There are two main advantages with CMOS sensors: First a hyperspectral image consists of spectral lines with a large difference in intensity; in a frame transfer CCD, the faint spectral lines have to be transferred through the part of the imager illuminated by intense lines. This can lead to cross-talk and whilst this problem can be reduced by the use of split frame transfer and faster line rates, CMOS sensors do not require a frame transfer and hence inherently will not suffer from this problem. Second, with a CMOS sensor the intense spectral lines can be read multiple times within a frame to give a significant increase in dynamic range.

We will describe the design, and initial test of a Fig.1: Schematic of Hyperspectral imager CMOS sensor for use in hyperspectral applications. This device has been designed to give as high a The challenge for Hyperspectral imaging is that there dynamic range as possible with minimum cross-talk. is a large variation in intensity between the different The sensor has been manufactured on high resistivity spectral bands that may be defined across the spectral epitaxial silicon wafers and is back-thinned and left range, as shown in Fig. 2. This causes two significant relatively thick in order to obtain the maximum problems; firstly the detector must be able to operate quantum efficiency across the entire spectral range. with a large range of signal intensities and secondly 2. Design Requirements: A hyperspectral sensor is care must be taken to avoid cross-talk of the high effectively an array of many linear imaging devices intensity spectral bands with those which are less each targeted at a different spectral band, as shown in bright.

39 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 This difference in intensities between the spectral optical and electrical components. The electrical lines becomes significantly more sever if shorter cross-talk is a much less significant issue for CMOS wavelengths are used (for example in Sentinel 4). imagers where there is no frame transfer required as part of the read-out process. Additionally the spectral response of the detector also tends to be lower at the edges of the spectral band 3. Design: The intention of this development was to which gives a further increase in the ratio of the produce a generic CMOS hyperspectral imager that could be readily adapted for different applications. signal level obtained in different spectral bands. A The main specification targets are as shown below. A typical plot of quantum efficiency (QE) of silicon brief description of the design is included in Table 1 sensors is shown below in Fig.3. This difference in below. signals means that the device must cope with a large dynamic signal range and is therefore very susceptible to cross-talk. Cross-talk can have both

Fig. 2: Ground Reflectance spectra. Fig. 3: Typical Back-thinned Silicon QE curve

Table 1: A Brief Description of the CMOS Hyperspectral Sensor Design Parameters

Parameter Value Comments Number of rows (spectral 256 lines) Number of olumns (spatial 1024 Any multiple of 512 columns can be made resolution) Pixel size 24 µm square Frame rate (full frame) 250 fps Windowing can allow faster rates. Windowing (ROI) Spectral direction Rows can be randomly selected only. Peak signal, “full well 100k or 300k Run time programmable, either global or row-by-row. charge”, QFW electrons

Shutter type Global pipelined Snapshot gives best motion-stopping. Rolling shutter can snapshot or include include CDS to reduce kTC noise. Row-by-row rolling or row-by- allows both read-with-reset or NDR (non-destructive row randomly readout). addressed. 40 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

Charge to Voltage 13 µV/electrons 10 µV/electrons at imager output pin. conversion gain at at 100k electrons QF W photodiode. setting Output type Analogue . 12 bit external ADC recommended

Number of output 8 One output channel for each group of 128 columns. channels

Fig. 4: 7T (8T) pixel design

A. Pixel design: There is some debate as to whether a any pattern of high and low gain rows. All actions global shutter is required for a hyperspectral CMOS from reset through integration to driving Vsample imager. As the conclusion is somewhat unclear the can be simultaneous on all pixels, giving a snapshot pixel for this device has been designed to operate as a shutter. Levels will stay on Vsample nodes to allow a baseline in global shutter mode but with an option to rolling readout of the stored image while the next run with CDS with a rolling shutter. image is integrating. If preferred the pixels can be read in a rolling shutter mode by setting line-by-line As a low cost 0·35 µm CMOS process was chosen for operation of the pixel controls in place of global this imager, the snapshot shutter must be operation. This mode can include CDS to reduce implemented by using switches and capacitors rather noise. than a pinned photodiode and transfer gate. This In addition rows can be randomly addressed and so leads to the use of two source followers in each pixel, rows where the signal level is high can be read out at in turn requiring a level shifter to give an output an increased frequency. voltage range suitable to read the desired full-well through the analogue chain. The circuit of each pixel For example the sensor could be operated with an is given above in Fig. 4. An n-well in p-epi diode is overall frequency of 100Hz for faint spectral lines but used for the photodiode PD and to give the choice of at 500Hz for the most intense spectral lines giving a two conversion gains, extra capacitance can be added further factor of x5 (or more if required) in the ratio of by setting GAIN to high to connect CE XTRA in the peak signal in different rows. When combined parallel with PD. This gives a 3 × factor on maximum with the capacitance switch this would accommodate charge and a 1/3 × factor on conversion gain. Each for a peak signal ratio of x15. row of pixels has an individual GAIN signal to allow

41 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 4. Manufacture: design requirements. These tests so far are with front A. Wafer Fabrication: As the pixel size is relatively illuminated operation which is non-ideal as the large and there is not high speed digital in the device sensor has a full mirror over the front surface to give this sensor was made using 0.35µm technology. In maximum response when operated in back order to be able to obtain good quantum efficiency at illuminated mode. the NIR end of the spectrum thick epitaxial silicon with a resistivity of approximately 1000Ω.cm was A dark frame shows a good uniformity with a used for the device manufacture with standard Gaussian distribution (see Fig. 5) with few defective 10Ω.cm. material as a backup. This enables the silicon ‘hot’ pixels. The total Dark Signal Non Uniformity to be depleted to a depth of greater than 10µm (DSNU) is approximately 9% of the mean dark signal. material). Preliminary measurements indicate that the mean dark signal is approximately 100 electrons per pixel B. Back Thinning: CMOS sensors have already been image at 250Hz and ±20°C. Fig. 6 shows a histogram successfully thinned [3] and these sensors will use a from a flat field image (with dark image subtraction) very similar process. Backthinning has started to give an indication of photo response non although results are not yet available. The 1000Ω.cm uniformity (PRNU). As can be seen the total PRNU material has a starting thickness of 14µm and is being including both gain and photo response non thinned to approximately 10µm uniformity has a standard deviation of 2.7%. As the front surface of the device is covered by a reflecting C. Assembly: Devices have been assembled in simple mirror giving very low detection efficiency this result PCB packages as the main objective of this seem surprisingly good. programme is to determine the electrical and electro- optical performance. The variation of dark signal with temperature and with integration time is as expected for a non-pinned 5. Test: A custom test set has been manufactured with surface. Plots of dark signal variation with time are the control signals provided by an Altera FPGA shown in Fig. 7 at +20°C and +25°C. An increase of through a Visual Basic interface. Data collection is dark signal of 50% between these temperatures is as carried out using Labview software via a Cameralink expected. Also note that at these signal levels the interface. The test set operates all 8 analogue channels linearity appears to be reasonably good although in parallel at 11MHz each giving a total data rate of detailed measurements of this have not yet been 88MHz to enable a maximum frame rate of 250Hz. made. One count corresponds to approximately 1.8 electrons. 6. Test Results: Preliminary testing has been carried out which shows that the sensor functions to the

Fig. 5: Dark Image Histogram; Fig.6: Photo Response Non-Uniformity; Fig.7: Variation of Dark signal with Temperature 42 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

6. Conclusions: once fully proven will take the place of CCDs for A Custom CMOS sensor has been designed for hyperspectral imaging applications. hyperspectral imaging and shown to perform as expected, although further characterization is 7. Outlook: Further customization and modifications required. It is anticipated that this type of sensor are expected to meet specific mission requirements the best possible way.

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43 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

Latest Developments in Infrared Space Detectors at Sofradir Philippe CHORIER, Anne DELANNOY SOFRADIR, 43-47 rue Camille Pelletan, 92290 CHÂTENAY-MALABRY, France Phone: +33.1.41.13.45.30, E-Mail: [email protected]

Abstract and accurate manufacturing and test means in order Sofradir is one of the leading companies that develop to manufacture space detectors and to answer the and produce infrared detectors. Space applications need of extensive testing and verifications generally have become a significant activity and Sofradir relies required in space domain. Thus, this paper, presents now on 20 years of experience in development and the technologies and the test means developed at production of MCT infrared detectors of 2nd and 3rd Sofradir for space applications. Then, a review of the generation for space applications. Thanks to its last developments conducted in visible and SWIR capabilities and experience, Sofradir is now able to wavebands (in particular for hyperspectral offer high reliability infrared detectors for space applications) is made. Finally, this paper presents the applications. These detectors cover various kinds of last developments made for applications in LWIR and applications like hyperspectral observation, earth VLWIR wavebands as well as the associated results. observations for meteorological or scientific purpose and science experiments. In this paper, we present a 2 Sofradir Space Activity: Technology and Means review of latest Sofradir’s development for infrared space applications. A presentation of Sofradir infrared 2.1 Sofradir technology for space applications: As detectors answering hyperspectral needs from visible for detectors for tactical applications, Sofradir up to VLWIR waveband will be made. In addition a detectors for space applications are constituted of particular emphasis will be placed on the different hybrids of a detection module made of MCT (Hg(1- programs currently running, with a presentation of x)CdxTe) material and a silicon readout integrated the associated results as they relate to performances circuit (ROIC) integrated in a dewar packaging. The and qualifications for space use. detection module is made by hybridization technique which uses indium bumps technology. In particular, 1. Introduction: Sofradir is involved in the the choice of the MCT material as a detection material development and manufacturing of 2nd generation has been made in France by Sofradir and LETI-LIR, as detectors for more than 20 years. This activity started it presents unique properties that make it an ideal with the development of the infrared detector for the candidate for most of the needs in infrared detection French military satellite Helios II that was completed in all the IR spectral bands. Firstly, the band gap can beginning of the previous decade by the deliveries of be tuned by just controlling the xCd/xHg ratio of the the flight models. Following this program, Sofradir alloy, making possible the entire infrared band to be space activity has increased with the completion of covered from visible to very long wavelengths (Zero numerous other programs. As a result, end of 2010, 28 band gap for xCd : 0.15). Secondly, fundamental flight models have been delivered, 5 of which are parameters such as lifetime are relatively high leading currently in operation on board satellites. Such an to low dark current and large quantum efficiency activity requires mature, robust, high performances (near 1) photodiodes. Moreover the performances of and reliable technologies. It requires also powerful detectors are only limited by the physics and

44 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 predictable by validated models in a large domain of Using the same technology for both kinds of temperatures and compositions. applications, space activity is pushing the performance of the technology trying to reach the The very large flexibility of these alloys makes better level of performance and reliability. Production possible: benefits from this situation as the performance of • the fabrication of a large variety of infrared Sofradir infrared detectors in general is pulled up. At detectors , in particular multicolor detectors the same time, production is pushing the which need multilayer epitaxies. manufacturing capacity and is bringing a large • to adjust the composition of the alloys to the number of infrared detectors manufactured and useful infrared band to get the ideal delivered. Space activity benefits from this situation composition xCd / operating temperature also as manufacturing of space detectors is based on couple to get the optimum performance for the proven, reliable and mature processes and production focal plane array. brings a large panel of detectors produced which are used as a reference for statistical analyses that are Among the other advantages recently pointed out necessary in space activity for reliability prediction as we can mention: an example. • an optimum light collection in backside illumination from the cut off of the detector to As a matter of fact, building blocks that are used for the near UV, including the entire visible the development and manufacturing of infrared focal spectrum, without any decrease of quantum plane arrays dedicated to space applications are: efficiency. • MCT detection layer deposited by liquid phase • A unique specificity in the semiconductor field epitaxy on CdZnTe substrate as large as 2.5’’ wafer for MCT avalanche photodiodes that can • Hybridization technology with indium bump exhibit very large gain at moderate bias, down to 15 μm pitch with detector format up to without any excess of noise (F(K) strictly equal 1280x1024 in production to 1). • Silicon readout circuit (ROIC) implemented with Sofradir design using advanced technologies with For space applications, Sofradir relies on the MCT resolution as low as 0.25 μm and 0.18 μm technology that is used for production of tactical detectors. In particular, the same production line is Based on all these building blocks, Sofradir delivered used and specific controls and process check points in 2010 more than 4000 infrared detectors for tactical are added in order to meet the quality assurance applications and 16 flight models for space requirements that are stringent for space applications. applications. This strategy enables to offer a real synergy between production activity and space activity. This synergy 2.2 Sofradir means for space applications: As can be illustrated by the following scheme: explained above, infrared detectors are manufactured using industrial facilities. Besides manufacturing of • production activity calls for production constraints the detectors, another stringent requirement for space like : large quantity manufacturing, production activity is the need to provide extensive testing of the capacity as well as increase of yield and detectors during development and during final flight reproducibility models production. For that purpose, through its • space activity calls for high performance activity, Sofradir has developed powerful and very technology and high reliability accurate tests means.

45 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 2.2.1 Spectral test benches: Spectral tests are made at 2.8μm. This test bench covers a spectral range from 0.4 Sofradir according to different main ranges : visible μm up to 2.8μm. (0.4 μm – 0.8 μm) and SWIR (0.8 μm– 3 μm) spectral range on one side and MWIR (3 μm – 5 μm) up to Above visible and SWIR spectral range, Sofradir has LWIR (8 μm – 12 μm) and VLWIR (12 μm –15 μm and implemented a spectral test bench based on InfraRed more) spectral range on the other side. Thus, Sofradir Fourier Transform (IRFT) method for measurements has implemented a spectral test bench adapted for of infrared detectors performances (Fig. 2.2). The measurements in the visible and SWIR spectral region methodology of measurement for this bench is based (Fig. 2.1). This bench is composed of the following on the comparison of an interferogram of signal elements: registered from a calibrated detector and from the detector under test when both detectors are • The Source is a quartz tungsten halogen illuminated by a light of a black body source through stabilized lamp which provides high level of a Michelson interferometer. This test bench enables to radiance from 0.4 to 2.8μm. obtain the following performances: • A Czerny-Turner Gratings Monochromator • Spectral range: 2 μm up to more than 14 μm composed of three different gratings to cover with possibility to make multi pixels the whole spectral band, order filters, and measurements (several thousand at the same variable width slits to adjust the compromise time) between radiance level and spectral resolution. • Resolution : 0.145 μm at 13.4μm (8cm-1) The slits are motorized and fully controlled by • Wavelength repeatability: < 5 nm Software/user. • Relative response: 2 % • Optical chopper combined with a lock-in amplifier to reduce the noise influence and enhance the detection limit. • Integrating sphere with a specific coating to have a high reflectance in the whole spectral band. The role of this element is to provide a lambertian and uniform source. • Reference detector (Pyroelectrical detector) for radiance control: the signal of this detector is recorded at the same time of the DUT in order to check the radiance level and to make a post treatment if necessary. This post-treatment ensures reliability in test conditions of +/- Fig. 2.1: Visible – SWIR spectral test bench 1.5%. • Acquisition system linked to a computer which besides drives the monochromator (slit width, gratings position, order filter position…)

The combination of the light source, the monochromator and the integrating sphere acts as a tunable uniform lambertian source between 0.4 and

46 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 high BRDF and surface homogeneity. As a matter of fact, irradiance relative accuracy is 0.15%, irradiance absolute accuracy is lower than 2.5% and blackbody temperature stability is better than 5 mK. This test bench allows measurements of the following radiometric parameters: max charge handling, responsivity, dark signal, 1/f noise, radiance response, linearity, saturation and blooming recovery, quantum efficiency. 3.2.3 Modulation transfer function test benches: In Fig. 2.2: infrared spectral test bench with Fourier transform methodology addition to spectral and radiometric tests benches, 2.2.2 Radiometric test benches: Extensive radiometric Sofradir has also developed an extensive test facility measurements capabilities are required for answering around MTF measurements which are always space applications needs. Thus, through its space considered as a critical performance to be addressed activity, Sofradir has settled different powerful for infrared space applications. Two test benches are radiometric test benches. According to the addressed available : one which has been initially developed for waveband, different test means are necessary. First of measurements in MWIR (Fig. 2.5) and which these tests benches is a radiometric test bench that capacities have been extended in SWIR and visible enables to measure detector performances in visible spectral ranges and one for MTF measurements in and SWIR waveband (Fig. 2.3). This radiometric test LWIR and VLWIR spectral ranges (Fig. 2.7). MTF bench is composed by the following main elements: measurements are made on a single pixel at a time by • a lamp mounted in an integrating sphere and moving the image of a knife edge in X and Y axes on controlled in radiance, the detector sensitive area. The illuminating source • a cooled chamber with baffles to prevent stray may be a blackbody (max 600°C) or a high flux lamp light. (Ceramic composite core at high temperature > 1500°C). Spectral filters can be added before knife This test bench allows measurements of the following edge to select the spectral band pass. Thus, Sofradir radiometric parameters in a large spectrum of has a complete set of test benches enabling to measure radiations (0.4 μm up to 2.8 μm) : defects, detector MTF of infrared detectors from SWIR spectral range sensitivity, photo-response non uniformity, offset and (and even visible) up to VLWIR spectral range. dispersion, linearity, dark current level, low frequency noise. The second kind of test benches that Sofradir 3 Developments for Space Applications From has implemented concerns high performance MWIR- Visible To Mwir LWIR-VLWIR radiometric test benches (Fig. 2.4). This 3.1 Visible – SWIR detectors for imagery and radiometric test bench is composed by the following hyperspectral applications: Sofradir has acquired a main elements: large experience in the field of SWIR detectors for • a lambertian black body with very fine regulations hyperspectral applications thanks to the first of temperature developments of its Saturn 1000x256 CTIA staring • a vacuum chamber containing the blackbody. array in the early 2000 in the frame of an ESA contract Vacuum allows reaching negative temperatures [1]. This experience has been extended to the visible with the black body. These tests benches comprise spectral range, thanks to a technology developed by black bodies having a temperature range from - Sofradir, called VISIR [2]. Thanks to these 30°C up to 100°C with an emissivity of 0.99 and a developments, Sofradir is now able to offer a complete 47 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 range of products, fully qualified for space range (0.9 – 2.5 μm) and with extension to visible applications concerning imagery and hyperspectral spectrum (0.4 – 2.5 μm). Main characteristics of these needs. The proposed products are named either products are described in the table below (some of the Saturn with a format 1000x256 (pixel pitch of 30 μm) characteristics are common as the MCT technology or Neptune with a format 500x256 (pixel pitch of 30 and the readout circuits of the detectors are the same μm). Both detectors can be proposed in SWIR spectral for both products).

Fig. 2.3 : Visible – SWIR radiometric test bench Fig. 2.4 : MWIR - LWIR - VLWIR radiometric test bench

Fig. 2.5: Visible, SWIR and MWIR MTF test bench; Fig. 2.6: MTF test bench principle; Fig. 2.7: LWIR and VLWIR MTF test bench

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Several configurations are available for Neptune and Saturn detectors : airborne configuration, space flight configuration, space flight configuration compatible with passive cooling (Fig. 3.1).

Fig. 3.1: Neptune and Saturn detectors available configurations : a) airborne configuration of the Saturn detector with a dewar and a cooler; b) Space configuration of the Neptune detector (500x256) with a dewar and a cooler adapted to space constraints; c) Space configuration of the Saturn detector (1000x256) compatible with passive cooling system

49 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Figure 3.2 :Cross-section=f(LET) and corresponding fit with a Weibull model for latch-up on two biases, showing a SEL threshold above 20 MeV/mg/cm².

More recently, Sofradir has completed the development and the qualification of the Saturn detector with a passive cooling configuration (with both versions of the Saturn detector: VISIR and SWIR). This detector is sealed under neutral atmosphere (He2) and is compatible with passive cooling, thanks to its high thermal conductivity on the backside of the package. The electrical interface is provided on the two sides of the dewar, as shown on the pictures above. The package can be screwed on the interface of Fig. 3.3: Saturn detector qualification versus shock the passive cooling system thanks to four holes. A response spectrum window with a specific anti-reflective coating ensures the optical interface with the IRFPA.

As a matter of fact in the frame of the various programs using these detectors, Sofradir has fully qualified its 500x256 (Neptune) and 1000x256 (Saturn) detectors for both SWIR and VISIR wavebands versus radiations according the following levels : dose rate up to 20 krad and protons fluency up to 2.6 1011 Fig. 3.4 : Saturn detector qualification versus random p/cm² with energy at 30 MeV and 60 MeV. An vibrations example of qualification measurement versus protons All these tests have been passed successfully with full irradiation can be found in [3]. Single event upset and operation of the detectors (both SWIR and VISIR latch-up sensitivity have also been studied. For that versions) before and after the tests. Manufacturing of purpose, heavy ions tests were performed with a SWIR and VISIR flight models was made in parallel of multi-particle cyclotron with variable energy. the qualification presented above and as a matter of Measurements were performed at room temperature fact, Sofradir successfully achieved the realization and (worst case compared to cool down temperature). Fig. delivery of more than 8 Saturn flight models (with 3.2 shows typical cross sections obtained on two both versions VISIR and SWIR) in 2010 for different biases of the ROIC, at different energies. A Weibull hyperspectral applications like the Italian PRISMA model has been used to extract the Latch-up mission for example. An example of the performances threshold. The detector has been demonstrated free of measured on one of these SWIR flight models is latch-up and single effect up to 20 MeV/mg/cm² and shown in Fig. 3.5. The detector exhibits a mean signal up to 75 MeV/mg/cm², the number of occurrence of to noise ratio (SNR) of 383 to be compared to a BLIP these effects is very low. SNR of 406 considering input flux and 100% quantum Finally, the detector has been qualified according to efficiency. Operability of the detector is also excellent shock response spectrum for a level of 800 g up to as presented in Fig. 3.5 (operability is higher than 10000 Hz (Fig. 3.3) and random vibrations for a level 99.94% with very few clusters of defects). of 1.5 g²/Hz in the range [100 Hz – 2000 Hz] representing a total integrated energy of 54 g rms (Fig. Sofradir has also delivered Neptune SWIR detectors 3.4). for many space applications (more than 6 flight models). This detector benefits also of all the 50 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 qualification tests results presented above and is compared to a BLIP SNR of 990 considering input flux therefore available as an off-the-shelf flight model and 100% quantum efficiency. Operability of the product fully qualified. An example of the detector is also excellent as presented in Fig. 3.6 performances measured on one of these SWIR flight (operability is higher than 99.99% with very few models is shown in Fig. 3.6. The detector exhibits a clusters of defects). mean signal to noise ratio (SNR) of 957 to be

Fig. 3.5: Saturn SWIR flight models characterizations (at 8 MHz, integration time = 4.4 ms, operating temperature =180 K, gain 30 fF, well fill = 25%) : a) SNR, b) operability (criteria = mean SNR/2), c) normalized spectral response

Fig 3.6: Neptune SWIR flight models characterizations (at 8 MHz, integration time = 3 ms, operating temperature = 150 K, gain 128 fF, well fill = 35%) : a) SNR, b) operability (criteria = mean SNR/2; output signal outside ±30%)

Finally, a last example of the use of the Neptune the design and definition of this detector has been detector with Sofradir MCT is the Phobos grunt made previously [4]. The detector that has been mission. Sofradir delivered recently for this mission a developed is composed of two MCT arrays with 15 Neptune flight model detector with the same μm pitch pixels hybridized on a custom ROIC (Fig. definition as presented above but with an extended 3.7). Cut-off wavelength of each MCT array has been cut-off wavelength up to 3.2 μm. In particular, optimized versus the following trade-offs : reduction Sofradir benefits from all the space heritage of of dark current, optimization of the spectral range Sofradir MCT technology as well as the qualification versus the mission need and operating temperature heritage of the Neptune and Saturn detectors so that between 180 K and 200 K. One MCT array has a cut- the flight models were delivered in a very short term off wavelength of 2 μm for band B10 (imagery at 1375 (less than 8 months). nm with Δλ = 30 nm) and B11 (imagery at 1610 nm with Δλ = 90 nm) and another one with 2.5 μm cut-off 3.2 SWIR imagery applications: Among the different wavelength for band B12 (imagery at 2190 nm with Δλ space programs conducted by Sofradir, the = 180 nm). development and the realization of the SWIR detectors for the Sentinel-2 satellite as part of the European GMES can be highlighted. Presentation of

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Fig. 3.7: Topology, photography of the MCT SWIR FPA developed for the Sentinel-2 mission (size ~21x12 mm²), view of the FPA integrated in its packaging

The ROIC has been designed with CTIA input stage be cooled at 180-200K by passive cooling. The package which is well-adapted to low fluxes encountered in design is robust to vibration and compatible with the SWIR in general and in this application in particular. launch vibration constraints (first vibration mode of It uses a 3.3V voltage supply with a 0.35 μm CMOS assembly is around 3.8 kHz whereas the maximum technology. The ROIC operates in a snapshot mode, vibration frequency at launch is 2 kHz). In order to with 3 independent integration times (one per band). optimize thermal conductivity, the MCT retina is Redundancy at pixel level, operated with a serial mounted directly onto the ceramic multilayer interface, has been implemented in order to optimize package. Two diode temperature sensors are included the operability of the detector and to guarantee a “0 to provide the MCT detector temperature. Electrical defect” detector for each channel. During integration interface is provided by a flex cable including a μD time, each pixel integrates the photodiode current and connector, plugged to the metal pins of the ceramic converts the resulting charge into voltage (CTIA input package. The MCT retina is connected to electrical stage). A single output amplifier provides the output lines by gold bonding. After the first design phase level of the selected pixels at a frequency close to 2.4 concluded successfully in 2010 by the CDR of the MHz. The ROIC uses Integration While Read (IWR) project, Sofradir started the manufacturing and the mode: the signal of frame N is read during integration delivery of the flight models. First models were time of frame N+1. The MCT detector is integrated delivered in 2010. Fig. 3.8 presents the typical into a sealed housing filled by helium to ensure measurement of SNR of one of these flight models in protection and reliability of the FPA during its lifetime function of the different channels (using TDI function (Fig. 3.7). This SWIR elementary detector is planned to with two pixels for B11 and B12 channels).

Fig. 3.8 Sentinel-2 flight model SNR characterizations (at 2.4 MHz, operating temperature = 190 K, well fill = 60%) for the different channels B10, B11 and B12

These measurements show the high quality of the meteorological applications two kinds of systems can performances reached with no defective pixels across be identified using imagery or spectrometry. These each line for the 3 different channels. two kinds of instruments require detectors operating in high wavelength bands (up to 15 μm) while having 4 Developments for Space Programs from LWIR To high radiometric and imaging performances. The VLWIR: The need in LWIR to VLWIR development in challenging issues in these long-wave spectral bands space activities is mainly driven by imagery, concern the quality of the material (Cd1-yZnyTe meteorological and scientific applications. Regarding substrate, epitaxial layer of Hg1-xCdxTe alloy) which

52 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 is a critical point to obtain high-quality detectors with dependence on the dark current density imposes low few defects and low response dispersion in bands operating temperature in order to get acceptable dark LWIR and VLWIR. The optimization of the currents: typical operating temperature range is 50- parameters at the material level is thus crucial. In this 60K for such low band gap detector. In order to paragraph, results of Sofradir MCT technology for manufacture these demonstrators, a readout circuit VLWIR needs are presented and then architectures of has been chosen among already existing ROIC. The the detectors that have been developed are presented goal was to have a demonstrator array with with their associated results. representative dimensions of the main missions’ requirement in VLWIR waveband, thus leading to a 4.1 Latest results of VLWIR detectors development: staring array with dimensions around 1 cm². Sofradir is currently conducting several space programs using VLWIR MCT technology. One of Thus, taking into account the needs especially in term them is the development and manufacturing of the of charge handling capacity, the readout circuit that detector for the SGLI mission for the Japanese space has been is a 320x256 format with 30μm pitch, with a agency. Another one concerns pre-development 36Me- gain. Fine electro-optical characterization of activities conducted in the frame of the development this demonstrator has been led at 50 K [6]. Particular of the next generation European meteorological performance that has been checked carefully is the satellites MTG with the support of ESA. Through MTF. Thus, MTF measurements in the X and Y these different programs, studies have been launched direction were performed by using a vertical and in order to develop and improve VLWIR MCT horizontal slit module with a 9μm narrow filter technology and to manufacture demonstrators (FWHM 0.18μm). As the bench operates at the enabling to test and to evaluate the performances of diffraction limit, the MTF is obtained by the technology. For the demonstrators, the exact deconvolution with a theoretical spot. Fig. 4.1 presents composition of the MCT alloy has been defined to the average MTF on three pixels which is 0.57 at reach a cut-off wavelength of about 15 μm at 50 K. nyquist frequency. This excellent result is achieved Such wavelength implies to work with very small thanks to the Sofradir silicon-like planar implantation band gaps (band gap energy: Eg ≅ 80meV) and thus, process which provides a well-controlled junction and brings severe constraints on composition control of diffusion lengths and enables sharp edge diode self rich mercury MCT layer (alloy composition x=0.2) and limited by its neighboring diodes even with cut-off on operating temperature control. The temperature wavelength as high as 15 μm.

Fig. 4.1: VLWIR MCT array (320x256 / 30 μm pitch ; 15 μm cut-off wavelength) average MTF on 3 pixels and theoretical MTF

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Fig. 4.2: Evolution of the dark current on the VLWIR FPA and of the diffusion limit model vs. temperature

The quantum efficiency was measured to be about drastically the photon background. Obtained results 65% for this demonstrator, indicating a good are given in Fig. 4.2 regarding the evolution of the technology mastery of the diffusion length and layer dark current and the comparison of this evolution to for the VLWIR band. the diffusion limit model versus operating Considering dark current, a challenging issue on the temperature and in Fig. 4.3 regarding measurement of technological development at such cut-off wavelength dark current and pixel map in dark current conditions is to obtain photodiodes whose dark current is at 60 K. As a conclusion, standard Sofradir dominated by diffusion current at such low technologies allowed the fabrication of VLWIR operational temperature. For this measurement, the detectors exhibiting excellent behavior with no excess retina is covered with a 0° field of view cold shield of shot noise and dark current down to 50K. (closed cold shield) at detector temperature to reduce

Fig. 4.3 : Dark current density histogram and pixel map at 60K for VLWIR FPA (320x256 / 30 μm pitch ; 15 μm cut-off wavelength)

4.2 Specific architectures of LWIR and VLWIR of having several detection circuits hybridized on the detectors same readout circuit. This can be achieved thanks to 4.2.1 Multi-hybridized structures for imagery the indium bumps hybridization process used at applications: Applications for meteorology or Sofradir, based on a unique reflow technique. imagery require specific architectures. For example, in This technique allows the MCT array to be accurately meteorological applications which need imagery, and automatically self-aligned on its silicon read-out several spectral bands are necessary, corresponding to circuit, and gives a perfect connection yield, enabling solar channels. This can lead at FPA levels to the need simultaneous multiple arrays hybridization on a

54 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 single silicon chip. As an illustration, two kinds of performance, each super-pixel is made of n x n square realizations are given hereafter with several detection subpixels and the readout circuit enables sub-pixel circuits hybridized on the same readout circuit. deselection. Realization and evaluation of such a structure has been made in the frame of the space programs run at Sofradir in VLWIR waveband (MTG pre-development studies and SGLI program).

More in detail, Sofradir has designed a detector test vehicle in order to evaluate the potential performances of detector for VLWIR sounding instrument in the frame of MTG pre-development studies. This test vehicle is an FPA composed by a Fig. 4.4: SGLI VLWIR MCT detector (size 6.25 x 5 mm²) specific readout circuit hybridized with an MCT array constituted by 66 x 66 super-pixels with a pitch of 90 μm, each super-pixels being composed of 3 x 3 sub- pixels with a 30 μm pitch. The cut-off wavelength of the test vehicle is 13.3 μm at 55 K. Regarding the readout circuit, it has been designed in order to answer the main need of sounding applications : high Fig. 4.5: Sentinel-2 focal plane array (SWIR FPA with 1298 charge handling capacity and high pixel frequency. pixels with 15 μm pitch) The main characteristics of the ROIC are the following The first one represents FPA manufactured for the ones: needs of SGLI program (Fig. 4.4). This retina includes two detection circuits for detection at 10.8 μm and 12.0 μm, hybridized on a single CMOS readout circuit. Each detection circuit is made of 20x2 square pixels of 140 μm. The MCT material and the photovoltaic technology are adapted to maximize response for the requested bandwidths: cut-off wavelengths of the 2 detection circuits are 12.6 and 13.4 μm at 55K. Another example of multi-hybridized structure is the Sentinel- 2 focal plane array presented previously in this paper (Fig. 4.5) which is implemented in this case for a SWIR FPA.

4.2.2 Large pixel size and sub-pixel technique: Among imagery and meteorology applications for Fig. 4.6 : Impact of deselection on responsivity and RMS LWIR and VLWIR spectral range, lots of applications noise for 11 super-pixels constituted of 9 sub-pixels are based on sounding instruments which principle is to perform an interferometric image of the scene to be The readout circuit has been designed to enable sub- observed. For this kind of instrument, large pixel size pixel deselection through a serial link in order to is necessary and high operability is required. As this improve operability of the test vehicle. This feature requirement becomes difficult to achieve when has been tested in order to validate the operability operating in very-long wave spectral bands, a way to improvement expected. Impact of sub-pixels overcome this issue is to use a super-pixel structure. deselection is illustrated in Fig. 4.6, for 12 chosen This means that, in order to optimize the overall super-pixels : defective ones, to see potential improvement with deselection and good ones, to see 55 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 performance change with deselection. The gain in terms of operability is significant as it can be seen that performance of super-pixels with high noise and/or low responsivity can be significantly improved.

In addition of this analysis, the following table presents the operability improvement that can be reached using the deselection function presented above. A maximum of 3 sub-pixels deselection per super-pixel is allowed in order to maintain a high Fig. 4.9: MTF of a VLWIR superpixel with 90 μm pitch super-pixel quantum efficiency and signal to noise along Y axis ratio. The results presented in this table show a high 5. Conclusions: The development and the detector operability which can be significantly manufacturing of infrared detectors for space improved thank to the deselection function. applications is demanding regarding several items : mature, high performance, robust, reliable and Another parameter that is important to consider is the producible technologies, skilled people, powerful and MTF. Indeed, it has been seen above that the MTF of a accurate manufacturing and test means. Last 30 μm pixel pitch detector in VLWIR waveband is developments concerned the qualification of space close to the theory but the question concerns now the detectors for visible and SWIR hyperspectral MTF of a superpixel of 90 μm pitch made with 9 sub- programs. In addition, the development of the SWIR pixels of 30 μm sub-pixel pitch (see Fig. 4.7). Fig. 4.8 detector for the Sentinel-2 applications has been and Fig. 4.9 presents the measured MTF of a super- completed and the program has come now to the pixel with 90 μm pitch. These measurements exhibit qualification and the manufacturing phase for the an MTF higher than 0.55 at Nyquist frequency (5.56 flight models. mm-1) which is very close to the theoretical value for a square pixel of 90 μm pitch. This result confirms the Regarding the other part of spectrum in LWIR and ability of Sofradir MCT technology (ion implantation VLWIR wavebands, most of the developments and planar technologies) for VLWIR detectors so that concerned the extension of the cut-off wavelength up the MTF of the detector is the highest performance. to 15 μm at least as well as the analysis of the performances of the technology. The results presented in this paper have shown the high level of performances which are reached for such detectors in this waveband. As a result, several programs are currently run with this MCT technology and such

Fig. 4.7: cartography of 30 μm subpixels for a super-pixel long wavelength. For example, Sofradir has of 90 μm completed the development phase of the detector for the Japanese space agency mission SGLI (using MCT with cut-off wavelength of 13.4 μm operating at 55 K) and is currently manufacturing the flight models for this program. As a conclusion, Sofradir has developed a large expertise for space activity covering all wavelengths from visible up to VLWIR. As a result, up to end of 2010, Sofradir has delivered 28 flight

models which 5 of them are currently operated on Fig. 4.8: MTF of a VLWIR superpixel with 90 μm pitch along X axis board satellites.

56 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Acknowledgments: The authors thank all the Sofradir [3] Latest results of Sofradir MCT technology for space teams, dedicated to quality work and won challenges, applications, L. Vial, P. Chorier, O. Gravrand, proc. which made Sofradir become a top-ranked key player SPIE, vol.7106, p.71061L-1 (2008). in the infrared field for space applications. The [4] Development of a SWIR multi-spectral detector for authors would like to thank also the European Space GMES/Sentinel-2, Aurélien Dariel et al., SPIE Proc., Agency (ESA), the French space agency (CNES) and Berlin 2009. the French MoD for their support through the [5] Development of a long wave infrared detector for different programs where Sofradir is involved. SGLI instrument, A. Dariel, P. Chorier et al, SPIE Proc., Florence 2007. References [6] LWIR and VLWIR detectors development at [1] Sofradir infrared detectors for space applications, SOFRADIR for space applications, B. Terrier, A. P. Chorier, M. Vuillermet, SPIE Proc vol[5978-42]., Delannoy, P. Chorier et al., SPIE Proceeding Vol. 7826, Bruges 2005. Toulouse 2010. [2] From visible to infrared: a new approach, P.Chorier, P.Tribolet, G.Destefanis, SPIE proceedings vol[6206-01] – Orlando April 2006.

3000 Pixel Linear InGaAs Sensor for the Proba-V Satellite Raf Vandermissen, sInfraRed 1. Introduction: The Belgian Proba-V min-satellite, between the lines may be minimized by orienting the currently under development by Qinetiq Space NV center PDA chip in the opposite direction of the two (Kruibeke, Belgium), will carry a multispectral Earth outer ones. Hence, while the pixels are not on one observing instrument based on the push-broom single continuous line, the three lines of the principle and is intended to deliver data from four individual PDA chips are still located within 1.4 mm wavelength bands in the visible and short-wave in the along-track direction, and a small overlap of infrared infrared (SWIR) bands over a wide swath of 2*75 pixels is provided in the adjacent regions. The 2250 km. The four wavelength ranges will be imaged assembly is realized in a custom-designed kovar through the same Three-Mirror-Anastigmat (TMA) package of ~103 mm length with 72 pins shown in telesocpe, currently under development at OIP NV Fig. 2 (left). The large number of pins is required to (Oudenaarde, Belgium). Due to the very large swath operate and read-out the three ROICs independently and corresponding field-of-view (FOV) of over 100º, for improved redundancy in case of failures during three identically equipped telescopes will be used, mission. Due to the tight pitch, two rows of wire imaging three partly overlapping parts of the full bonds on a 50 µm pitch are used to connect the ROIC FOV. In this paper, we will describe the design of the chips to the PDA fan out, shown on the right hand SWIR sensor developed to image the 1610 nm side of Fig. 2. wavelength band in the three telescopes. 3. The Photodiode array and read out iC: The SWIR 2. Device Architecture: Due to the required imaging band of the Proba-V mission is defined with a center length of over 2700 pixels, it was decided to make the wavelength of 1610 nm, which makes InGaAs, with a device in three sections, each consisting of a Read-Out quantum efficiency (QE) of more than 60% at that Integrated Circuit (ROIC) chip and Photodiode Array wavelength, the preferred choice of material for the (PDA) chip with 1024 pixels on 25 um pitch. The sensor. The response spectrum of InGaAs has a ROIC chip has been custom designed for the mission temperature dependence of ~0.9 nm / K and the as is illustrated in Fig. 1, the photodiodes on the PDA slope of the QE is only ~0.1% /K at room chips are placed off-center, so that the distance

57 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 temperature for this wavelength. The signal chain of within an order of magnitude at the beginning of the ROIC (Xenics XRO-3508) is illustrated in Fig. 3 the design phase and a possibility for fine tuning and consists of several steps. the gain in flight was requested. • The photocurrent to voltage conversion is done in • On-chip correlated double sampling (CDS) is a Capacitive Transimpedance Amplifier (CTIA) applied in a separate gain stage, which also stage with selectable capacitors (capacitances increases the internal signal swing with a factor of ranging from 5fF to 830fF), yielding a total of 16 about 1.6. The purpose of the CDS is to reduce the different gain settings. The optical intensities and influence of kTC noise from the resetting of the integration times to be imaged were known CTIA amplifiers [7].

Fig. 1: Outline of device in package without lid and window. Left: The three ROICs and PDAs placed inside the package. Right: Partial overlap between the PDAs. The horizontal dotted lines show the off-center location of the line of photosensitive elements, their distances and the overlap between two PDA chips.

Fig. 2: Left- The complete populated package without lid. Right-fine pitch wire bonding of PDA to ROIC in overlap area. • In order for the chip to be able to operate in loops. Each gain stage and the S/H stage need Integrate-While-Read (IWR) mode, the next step is reference voltages, indicated as the inputs on the the Sample-and-Hold stage (S/H). This is a positive sides of the OpAmps of the gain stages. passive stage in this device, containing only These voltages may be generated by an internal switched capacitors. In this stage, the signal is also bandgap-reference subcircuit inside the ROIC chip converted from single ended to differential. itself, or applied externally. For the Proba-V mission, they are applied externally so that each of the three • The last step inside each pixel is the column chips receives exactly the same reference voltages. buffers, which multiplexes the signals onto two output buses. The planar nature of high-fill factor InGaAs image sensors makes them susceptible to blooming, a • Finally, a strong output amplifier is used for off- phenomenon where the charge form one over chip connections. saturated pixel transfers to its neighbors – which in An important feature of this design is that for all steps turn saturates and transfer their excess charge to their inside a pixel, an Auto-Zero (AZ) cycle is applied neighbors. To avoid blooming, we have implemented during reset in order to reduce CMOS offsets that an anti-blooming subcircuit for each pixel in the occur in every gain stage. The AZ functionality is design. Without anti-blooming, the pixels adjacent to implemented by extra switches in the CTIA feedback

58 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 the one being over saturated would have increased Despite CDS, the noise per pixel is a function of the their apparent responsivity. gain, as shown in Fig. 5:5, where the output referred noise per pixel is plotted against the size of the 4. First Results: An Engineering-Ground-Support- feedback capacitor for two different integration times. Electronics (EGSE) system has been constructed that The gain used in the Proba-V mission will be near can read out the image from the three ROICs in 500fF, where the measured noise is below 1mV. With parallel while at the same time providing a common a full differential signal swing of over 2.2 V, this trigger pulse for the simultaneous snap-shot means that the dynamic range is over 1:2000 after integration mode. Fig. 4 shows the image of a rolling correction for the dark current. world map with a few added test targets. This image is completely un-corrected. The AZ and Acknowledgements CDS subcircuits provide this image sensor with This sensor was designed and manufactured under remarkably low non-uniformities, both in dark and in ESA contract 3-12441/08/NL/EM. Several partners photoresponse. contributed to the work and we would like to thank the following persons Alex Short, Luca Maresi and For the dark signal non-uniformity (DSNU), we Matteo Taccola from ESA, Tanja Van Achteren and measure 0.1% of the full signal swing and for the Stefan Livens from VITO, Wim Dams and Lieve De Photo-Response Non-Uniformity (PRNU), a similar Vos from OIP for many fruitful discussions Georg small value of 0.2%. The dark current per pixel is here Israel and Hakan Sakman from Cmosvision for the approximately 0.4 pA with a reverse bias of 160 mV. help with the design of the ROIC Yvan Paquin of PNL The signal non- linearity is below 0.2% when Innotech for the help with packaging solutions, and calculated over the 10% to 90% range of the full signal finally, Peter De Ruytere , Peter Hooylaerts and Koen swing. The reason for such good values of the Vanhollebeke for the help with the EGSE and uncorrected image is first that the internal amplifiers manufacturing. are very powerful and secondly that the AZ and CDS subcircuits provide on-chip image processing. However, this comes at a cost of high internal power consumption. The full assembly as shown in Fig. 2 requires nearly 1W of driving power.

Fig. 3: Overview of signal chain in ROIC XRO-3508

59 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

Fig. 4: First light image from Proba-V sensor and EGSE setup. The three partially overlapping sections of the image are clearly visible, as is the difficulty of illuminating the 1m wide object uniformly.

Fig. 5: Noise (in [V]) as a function of feedback capacitor size.

References [5] International Standards Organisation (ISO) (2007). [1] Ettenberg, M.H., Brubaker, R.M., Blessinger, M.A. , . & Burzi, V.J. (2005). Infrared Technology and [6] Enz, C.C. & Temes, G.C. (1996). Proceedings of the Applications XXXI 5783, 21-31. IEEE 84, 1584-1614. [2] Brubaker, R.M., Ettenberg, M.H., Onat, B.M., [7] Oliaei, O. (2003). Circuits and Systems I: Masaun, N. & Dixon, P. (2006). Infrared Technology Fundamental Theory and Applications, IEEE and Applications XXXII 6206, 620604+. Transactions on 50, 1198-1202. [3] Dixon, P., Masaun, N., Evans, M., Mchale, J.U., [8] Pimbley, J.M. & Michon, G.J. (1991). Circuits and Trezza, J. & Ettenberg, M. (2009). Airborne Systems, IEEE Transactions on 38, 1086-1090. Intelligence, Surveillance, Reconnaissance (ISR) [9] Hopkinson, G.R. & Lumb, D.H. (1982). Journal of Systems and Applications VI 7307, 730706+. Physics E: Scientific Instruments 15, 1214-1222. [4] Lucke, R.L. (1998). APPLIED OPTICS 37, 7248- 7252.

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60 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Single Photon Detection using InP/InGaAs Avalanche Diodes Mark A. Itzler, Mark Entwistle, and Xudong Jiang Princeton Lightwave Inc., 2555 US Route 130 South, Cranbury, NJ 08512 USA

1. Introduction: The detection of single photon at design improvements [4, 5], the two dominant short-wave infrared wavelengths near 1.5 μm is a mechanisms determining the DCR―i.e., trap-assisted critical requirement for many photonic applications, tunneling in the InP avalanche multiplication layer and significant progress has been realized in the and thermal generation in the InGaAs absorption performance of InP/InGaAs single photon avalanche layer―have been reduced to provide lower DCR at a diodes (SPADs) to provide this capability. The basic given PDE. In Fig. 1, we illustrate state-of-the-art tradeoff between dark count rate and photon detection DCR vs. PDE performance for our commercial efficiency is now adequate to support many InGaAs/InP SPADs. The best of these devices applications such as quantum information processing exhibits sub-kHz DCR for PDE as high as 25%, [1], free-space communications [2], and single-photon which is the highest performance reported to date imaging [3], and timing jitter associated with SPADs under comparable operating conditions. has also been demonstrated to provide very good 1E+4 1E-5 performance. Historical limitations on photon Dark Count Probability(ns 1550 nm counting rates caused by the afterpulsing phenomenon T = 218 K in SPADs are being circumvented, with commercial products now supporting count rates of at least 50 1E+3 1E-6 MHz and lab experiments demonstrating the viability of GHz count rates. SPAD device technology has Dark Count RateDark (Hz) -1

evolved to the point where large-format imaging ) arrays can be fabricated with excellent yield and 1E+2 1E-7 uniformity, and these devices show tremendous 0% 5% 10% 15% 20% 25% 30% 35% Photon Detection Efficiency promise for further scaling in pixel count and pitch. Finally, recent work on monolithic self-quenching Fig. 1: DCR vs PDE for PLI InP/InGaAs SPADs. SPADs has provided much simpler device operation Another important attribute of SPAD performance is by eliminating the complex electronic circuitry the accuracy with which the photon arrival time can generally required for SPAD operation, and these new be determined, i.e., the timing jitter. The principle devices promise a low-cost, easily deployable platform contribution to the jitter is generally fluctuations in for photon counting at short-wave infrared the amount of time required for the avalanche wavelengths. amplitude to build up to a pre-set threshold for 2. Fundamental SPAD performance: SPADs are detection. InP-based SPADs can provide 100 ps operated at an excess bias Vex above the breakdown timing jitter fairly routinely [6], and <50 ps voltage Vb in the so-called Geiger mode, in which performance has been demonstrated with good avalanche breakdown can give rise to a readily devices and well-designed circuitry [7]. detectable macroscopic pulse of current in response The last of the basic SPAD performance parameters is to the absorption of just a single photon. Larger Vex afterpulsing, in which carriers trapped by material will increase the photon detection efficiency (PDE) defects during one avalanche event can be detrapped but at the expense of inducing a higher dark count at a later time and induce dark counts that are rate (DCR). Managing the tradeoff between these correlated to the initial avalanche. Afterpulsing can two parameters is one of the fundamental challenges be eliminated by waiting for all carriers to detrap of SPAD design. Through device modeling and before re-arming the SPAD, but this long “hold-off” 61 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 time leads to low count rates. Since many especially when photon arrival times are known, as in applications for SPADs now require higher count many communications applications. However, fast rates, afterpulse mitigation has been a dominant gating poses the challenge of suppressing the large focus of recent work. capacitive transients that result from sub-nanosecond rise and fall times required for rapid switching of the 3. Higher frequency SPAD operation: There are a excess bias on the SPAD. We have performed recent number of possible strategies for afterpulse mitigation work to extend a method of transient cancellation at higher count rates, but the only recent efforts that using matched delay lines [9], illustrated in Fig. 2, to have proven successful are those that have focused on provide 1-ns gating at higher rates than possible in the reducing the amount of charge trapped per avalance past. With this approach, we can now achieve 50 by minimizing the avalanche charge flow. One MHz photon counting with modest afterpulsing of effective method for reducing avalanche charge flow 2.5% at 10.8% PDE, representing a 5–10X increase in is to use extremely short excess bias gates. This gate frequency relative to past results with this approach is conducive to high frequency operation, technique.

Fig. 2: Matched delay line concept (at left) for cancellation of capacitive transients caused by high- speed gating of the SPAD. PLI’s turn-key single photon receiver (at right) employs this concept to achieve 50 MHz photon counting.

Other laboratory schemes have shown the feasibility 10.5% PDE [10]. Both of these high frequency of much higher counting rates. One approach invokes techniques rely on periodic gating and fairly narrow a “self-differencing circuit” for transient cancellation. frequency ranges of operation for a given hardware The signal from each gate is put through a 50:50 implementation. It is significant to note that even splitter, and one-half of the signal is delayed by one these highest SPAD operating frequencies (~2 GHz) gate period and subtracted from the non-delayed half are being achieved with PLI devices of the same of the signal from the next gate. In this way, identical pedigree as those used in earlier experiments limited transients from each gate are cancelled, leaving just to vastly lower repetition rates (e.g., ~1 MHz). While the signal produced by an avalanche. The most recent high quality devices are a prerequisite for high-speed results of this technique have shown ~1.4% operation, circuitry and signal processing approaches afterpulsing at 11.8% PDE for a gate repetition rate of are also critically important in determining end 2 GHz [8]. Another recent scheme has been to avoid performance. transient generation altogether by gating with a 4. Single-photon detector arrays of 3D LIDAR purely sinusoidal gate signal that can be eliminated imaging: An area of dramatic recent progress with from the output signal by narrow notch filtering, InP/InGaAs SPADs is the demonstration of large- leaving just the avalanche signal. 2 GHz sine wave format focal plane arrays (FPAs) with excellent yield gating has most recently shown 3.4% afterpulsing at 62 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 and uniformity. We have developed 32 x 32 FPAs for module. Independent time-of-flight counters in single-photon 3D LIDAR imaging at 1.5 μm in which every pixel provide 13-bit time-stamps indicating all 1024 pixels are operable and provide <50 kHz when photon arrivals are sensed, and framed readout DCR (see Fig. 3) at an average PDE of ~22% with of this time-stamp data allows for the generation of modest cooling to -20ºC [11]. These FPA modules are 3D point cloud data and associated high-resolution comprised of a number of critical sub-components, 3D imagery. Because each pixel records only a single including a photodiode array (PDA) incorporating time-stamp per frame, we have designed ROICs with SPAD pixels; a CMOS readout integrated circuit very fast readouts to provide frame rates (ROIC) for pixel-level electrical interfacing and FPA- approaching 200 kHz for LIDAR range gate level control; a GaP microlens array (MLA) to ensure durations of 2 µs. With such high frame rates, high fill factor; and various packaging sub- intensity data from multiple frames can be rapidly components to define electrical, mechanical, and acquired. optical interfaces to the overall hermetically sealed

Fig. 3: Dark count rate (DCR) performance map (left) of all 1024 pixels of a 32 x 32 InGaAs/InP (1.55 μm) GmAPD FPA operating at 253K, with DCR in kHz. The array has 100% pixel operability, with all pixels having < 50 kHz DCR, as seen in the histogram (center). The inset (right) shows the packaged FPA.

5. Self-quenching negative feedback avalanche arming. To constrain afterpulsing, we must rely on diodes: In a recent effort to reduce the complexity of the negative feedback and the elimination of chip- SPAD operation, we have developed self-quenching level parasitics to reduce avalanche charge flow. The SPADs that will execute the entire Geiger-mode NFADs are particularly attractive for their potential operating cycle of arming, avalanching, quenching, scaling to configurations of large numbers of and re-arming with the application of just a simple multiplexed devices that can act as a solid-state dc bias [12]. This performance is accomplished by photomultiplier, analogous to a microchannel plate. using the chip-level monolithic integration of In Fig. 4, we show a micrograph of NFADs in a 4 x 4 “negative feedback” elements that counteract the configuration with output lines connecting the inherent positive feedback of the avalanche common anodes of all 16 devices; the substrate photodiode impact ionization process; we refer to provides a common-cathode connection. these devices as negative feedback avalanche diodes (NFADs). In return for the very simple operation of The highly reproducible avalanches resulting from the these devices, a key trade-off to manage is the negative feedback provide discretized signals from inability to limit afterpulsing by imposing a user- each active region that are added when multiple selectable hold-off time between quenching and re- photons are sensed simultaneously. This behavior 63 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 results in photon number resolution that is not [4] J.P. Donnelly, E.K. Duerr, K.A. McIntosh, et al., possible using discrete SPADs. IEEE J. Quantum Electron. 42, 797 (2006).

[5] X. Jiang, M.A. Itzler, R. Ben-Michael, and K. Slomkowski, IEEE J. of Sel. Topics in Quan. Electron. 13, pp. 895 (2007). [6] A. Tosi, A. Dalla Mora, F. Zappa, S. Cova, M.A. Itzler, and X. Jiang, Proc. of SPIE 7222, 72221G (2009). [7] M. A. Itzler, R. Ben-Michael, C.-F. Hsu, K. Slomkowski, A. Tosi, S. Cova, F. Zappa, R. Ispasoiu, J. Mod. Opt. 54, 283 (2007). [8] D.S Bethune and W.P. Risk, IEEE J. Quantum Electron. 36, 340–347 (2000). Fig. 4: Micrograph of 4 x 4 NFAD array showing [9] Z.L. Yuan, A.W. Sharpe, J.F. Dynes, A.R. Dixon, common-anode electrical connections and A.J. Shields, Appl. Phys. Lett. 96, 071101 (2010). References [10] N. Namekata, S. Adachi, and S. Inoue, IEEE Phot.

[1] N. Gisin, G. Ribordy, W. Tittel, and H. Zbinden, Tech. Lett. 22, 529–531 (2010). Rev. Mod. Phys. 74, 145 (2002). [11] M.A. Itzler, M. Entwistle, M. Owens, et al., Proc. of

[2] Special issue on “Free-space communication SPIE 7808, 7808-10 (2010). techniques for optical networks”, IEEE LEOS [12] M.A. Itzler, X. Jiang, B.M. Onat, and K. Newsletter 19, 6 (2005). Slomkowski, Proc. of SPIE 7608 760829 (2010). [3] M.A. Albota, B.F. Aull, D.G. Fouche, et al., MIT Lincoln Laboratory Journal 13, 351 (2002).

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64 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 SAGEM – REOSC contribution to Indian Remote Sensing Programs Eric RUCH, Sagem Défense Sécurité, REOSC High Performance Optics Department [email protected]

1. Introduction : SAGEM – REOSC has been +15°C and +25°C and lenses have to withstand contributing to the development of the Indian storage temperatures between –30°C and +60°C. The Remote Sensing program for more than 20 years and Fig. 2 shows the optical design. Each lens assembly is will be described in this article by four relevant composed of ten lenses, made of very different projects, the lens objectives LISS and OCM and the glasses, and two filters off axis telescope IRS 1C and IRS P5.

2. Lens Objective Systems 2.1 LISS: SAGEM-REOSC delivered to ISRO the high precision lenses for the LISS camera that have been operating on board of IRS 1A, 1B and 1C.

The main requirements of these lenses are the following:

• Focal length : 350 mm • Aperture : F / 4.35 • Field of view : 10° • 4 Spectral bands : 520 – 590 nm 620 – 680 nm 770 – 860 nm 1550 – 1700 nm Fig. 1: LISS Objectives • Image quality : MTF > 0.7 at 50 line pair / mm In order to achieve these very tight requirements, • Distortion, image formats registration and image REOSC has included in the design a dedicated format stability below 1 µm spheroparabolic lens and developed a micro- 2.1 Ocean Color Monitoring : In 1998 and 1999, polishing technique allowing the polishing of the SAGEM - REOSC supplied to ISRO two sets of eight parabolic surface with a very accurate and repetitive lens assemblies to be used for the Ocean Colour quality, detailed in Fig. 3. Monitor mission (OCM). All lenses have a 20mm focal length and operate over a very wide field of 3. Unobscured Mirror Telescopes view angle (86°). Each set of lenses covers the visible range using eight narrow spectral bands, one for each 3.1 Three Mirror Anastigmat IRS-1C: In 1995, lens, distributed from 412nm to 865nm. The eight REOSC delivered a Three Mirror Anastigmat (TMA) lenses of one set are matched: focal length better than telescope for a high resolution space camera of 1 ±0.01%, image format better than ±2µm, distortion meter focal length, F/4 relative aperture and +/- better than ±0, 45µm for each point of the field of 2.125 by +/- 0.425 degrees object field angle. view. All these requirements must be kept within an operating temperature range comprised between 66 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

Fig. 2 : Optical Layout of the OCM objectives

Before micro-polishing After micro-polishing (final state) Surface error ≅ 3µm RMS Surface error ≅ 20nm RMS , radius error < 25µm Fig. 3: Interferogram of the front parabolic surface

Final Obtained Performances Requirement Obtained EFL values 20.0 ± 0.1mm Min = 20.0068mm Max = 20.0080mm EFL matching ±2µm ±0.6µm Format matching ±2µm ±1.1µm Distortion value < 0.02% Max = 0.02% 1 Distortion matching < ±0.3µm ±0.45µm 1 Central wavelength 8 specified values ±0.5% Compliant values 0.1% < difference w.r.t. spec.< 0.45% Spectral bandwidth 20nm ±2nm (B1 → B6) 18.3nm < bandwidth < 20.6nm 40nm ±4nm (B7 → B8) 38.7nm < bandwidth < 37.9nm B1 : > 57% B1 : 65% Transmission B2 : > 64% B2 : 71 B3 → B5 : > 68% B3, B4, B5 : 80%, 78%, 81%

67 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 B6 → B8 : > 70% B6, B7, B8 : 82%, 83%, 84% Non uniformity of < 15% 12.5% < measured values < 15% illumination Veiling glare < 2% Compliant values B1 → B5 : > 60% B1, B2, B3, B4, B5 : 66%, 63%, 65%, 63%, 69% MTF at 50lp/mm B6, B7 : > 55% B6, B7 : 64%, 64% B8 : > 50% B8 : 56% Change in < ±1µm Compliant values collinearity

Fig. 4: OCM Lens Assembly (left) and front parabolic lens (right)

Fig. 5: TMA Mirrors (left) and image of Washington DC taken by IRC 1C (right) The entrance pupil of the telescope was 250 mm in 3.2 Three Mirror Anastigmat IRS P5: The following diameter. New techniques such as direct off-axis step was the manufacturing of the TMA of IRS P5 computer controlled polishing and interferometric with optics about 2.5 times larger than those of IRS assisted alignment have been developed and 1C. successfully used for producing these optics in less The main requirements of the telescope are the than 15 months. The mirrors were not lightweighted following: and delivered to ISRO without the interface fixations pads. IRS 1C was launched on 28 December 1995, • Focal Length : 2 meters just one year after the delivery of the mirrors and • Aperture : ∅ 500 mm provided image with a ground resolution of about 5 • Field angle : 2.6 x 0.3 degrees meters. • Image Quality : 40 nm RMS WFE over the whole field of view

68 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

Fig. 6: TMA Mirrors (left) and TMA during integration phase (right)

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69 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

70 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

71 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Overview of Teledyne Judson Technologies’ Contribution to RS Joseph Kimchia), Kai Songa), Henry Yuana), Mike Sullivana), Gary Apgara), Mark Sedivaa), Joe Changa), Varsha Nalavadea), Joyce Laquindanuma), Louis Kilmera) James Beleticb), Richard Blankb), Jagmohan Bajajb) a)Teledyne Judson Technologies, 221 Commerce Drive Montgomeryville, PA 18936 USA b)Teledyne Imaging Sensors , 5212 Verdugo Way Camarillo, CA 93012 USA

ABSTRACT various material types, operated at various This paper reviews Teledyne Judson Technologies’ temperatures and with various cutoff wavelengths. contribution to remote-sensing. For over 30 years, The photo-detector materials include Ge, InGaAs, Teledyne Judson Technologies has developed state- InAs, InSb, HgCdTe, Si, PbS, and PbSe. Focal plane of-the-art infrared sensor technologies and supplied arrays are produced from InGaAs, InSb, and many types of infrared sensor products to a variety HgCdTe to cover the near-infrared (NIR), of space remote sensing programs, covering almost shortwave (SWIR), mid-wave (MWIR), long-wave the entire infrared spectrum from near-infrared to (LWIR), and very long-wave (VLWIR) infrared very longwave infrared. These sensors are based on spectrum. These detectors operate in a wide various infrared materials, including HgCdTe, temperature range, from room temperature for InSb, InGaAs, InAs, Ge, Si, PbS, and PbSe. These NIR and SWIR, thermoelectrically cooled sensors may be single elements, linear arrays, and temperatures, such as 1 to 4-stage TE coolers two-dimensional arrays, all integrated with the (TECs) for SWIR and MWIR, to cryogenic and most advanced packaging, cryogenic cooling, closed cycle cooler temperatures for MWIR and optics, and electronic technologies. LWIR. Fig. 2 shows TJT FPA products covering a broad range of spectral wavelengths, operation 1. Introduction: Teledyne Judson Technologies’ temperatures, and material types. The IR detectors infrared sensor products contribute to remote are integrated with optics, cold shields, electronics, sensing by detecting signals emanating from the cooling, and packages to form the IR sensor earth’s surface (land and ocean) and atmosphere. subsystem. Our infrared sensors are used in a variety of remote sensing instruments onboard space-borne Teledyne Judson Technologies has developed satellite platforms and airborne platforms (aircraft many types of detector arrays utilizing a variety of and balloons). detector materials for remote sensing applications. Depending on the remote sensing mission, spectral For more than three decades, Teledyne Judson wavelength band of interest, sensing target size, Technologies (TJT) (formerly known as Judson distance, signal information and image resolution, Technologies, and prior to that EG&G Judson) has TJT can match the spectral band by using the been advancing infrared (IR) photo-detector sensor appropriate IR material, and design the IR detector technology and producing high-performance to meet the format and performance requirements. infrared detectors, linear arrays and focal plane This includes single-element detectors, linear arrays (FPAs), as well as packaging and integration arrays, variable size arrays, quadric arrays and 2-D technologies, for space and airborne remote small pixel arrays. This paper presents a highlight sensing applications. Teledyne Judson of TJT selected space programs on space-borne Technologies offers custom designed IR detector instruments for weather satellites and atmospheric arrays that cover the IR spectrum from 0.75µm to monitoring, as well as airborne remote sensing 22µm. Fig. 1 shows spectral detectivity (D*) plots instruments. The remote-sensing work at our for TJT standard IR detector product lines of

72 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 sister division, Teledyne Imaging Sensors (TIS), is administration (NOAA), see Fig. 3. All the detector also briefly reviewed. types are photoconductive HgCdTe operating near 100K. GOES satellites are in a geosynchronous orbit, 2. Teledyne Judson Technologies’ Space- which allows them to hover continuously over one borne and Airborne Remote Sensing Highlights: position on the surface. Table 1 lists some of TJT’s previous space programs. Teledyne Judson Technologies has demonstrated the The geosynchronous plane is about 35,800 km full capability of flight hardware design, prototype (22,300 miles) above the Earth, high enough to development, qualification testing, fabrication and allow the satellites a full-disc view of the Earth. assembly technology to meet space mission Because they stay above a fixed spot on the requirements. surface, they provide a constant vigil for the atmospheric "triggers" for severe weather 2.1 IR Instruments for Weather Satellites conditions such as tornadoes, flash floods, hail storms, and hurricanes. When these conditions 2.1.1. Geostationary Operational Environmental develop, the GOES satellites are able to monitor Satellite (GOES) Series: Teledyne Judson storm development and track their movements. Technologies developed high sensitivity water GOES satellites have been operating over the past vapor imagers and sounder sensors [1] for GOES two decades. satellites of National Oceanic and Atmospheric

Fig. 1: Spectral D* of Teledyne Judson Technologies Detector products

73 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

Fig. 2 Teledyne Judson Technologies FPA products

Table 1. Selected Remote Sensing Programs at Teledyne Judson Technologies

MISSION APPLICATION DETECTORS END USER Weather Satellites INSAT-Series Weather/Communications HgCdTe ISRO GOES Series Civilian Weather Satellites HgCdTe NOAA/NASA TIROS Series Meteorological Research HgCdTe NOAA/NASA MTSAT-Series Japanese Weather Satellites HgCdTe JAXA METSAT Weather Research HgCdTe ISRO INSAT 3D Remote Sensing HgCdTe /InSb/InGaAs ISRO COMS-1 S. Korea Weather Satellites HgCdTe KARI Atmospheric Monitoring HALOE-UARS Ozone Research InAs NASA Langley IMG-ADEOS Greenhouse ResearchHgCdTe /InSb JAXA SABER-TIMED Atmospheric Chemistry HgCdTe /InSb/InGaAs NASA ORBVIEW-2 Earth Resources Pyroelectric Lithium Orbital Sciences Tantalate IASI-METOP Meteorology/Climatic Studies HgCdTe EUMETSAT/CNES SOFIE-AIM Study of the Mesosphere HgCdTe, Ge, Si NASA ACE-SciSat-1 Atmospheric Chemistry InSb CSA Planetary Science Missions GALILEO Jupiter Probe Pyroelectric Lithium JPL Tantalate MARS SURVEYOR Mars Surface Probe Pyroelectric DLATGS JPL CHANDRA X-Ray Telescope Pyroelectric Lithium NASA Tantalate NEAR Asteroid Spectroscopy Ge NASA/APL MUSES-CN Asteroid Spectroscopy Multiplexed InGaAs 256E JPL MARS ROVER Mars Resources Pyroelectric DLATGS NASA CIVA Comet Spectroscopy Multiplexed MCT FPA IAS CRISM Mars Reconnaissance Orbiter Multiplexed MCT FPA NASA/JPL/APL

74 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 2.2 IR Instruments for Space-borne Atmospheric Monitoring

2.2.1 Halogen Occultation Experiment (HALOE): Teledyne Judson Technologies supplied InAs sensors for the HALOE instrument on board of the UARS satellite. In 1991 The Upper Atmosphere Research Satellite (UARS) began its study of the chemistry and physics of the Earth's atmosphere. UARS data is used to create global maps of ozone- destroying chemicals and to better understand the Fig. 3: Teledyne Judson Technologies provided processes related to ozone depletion. By 1994, UARS' sensors for GOES Satellites for remote sensing the comprehensive data set provided conclusive Earth's weather, flooding and storm [2] evidence that human-made chemicals are 2.1.2. Indian National SATellite (INSAT) Series responsible for the annual Antarctic ozone Weather Satellite: Teledyne Judson Technologies depletion. supplied to Indian Space Research Organization 2.2.2 Interferometric Monitor for Greenhouse Gases (ISRO) IR sensors for the INSAT series Satellites. (IMG): The Interferometric Monitor for Greenhouse Over the past decade TJT supplied MWIR Imager Gases (IMG) Program was an earth observing and Sounders utilizing InSb, LWIR Imagers, instrument on the Advanced Earth Observing Sounders and Water Vapor arrays utilizing Satellite (ADEOS) for Japan. The instrument was a HgCdTe, and SWIR arrays utilizing InGaAs. space-based FTIR which incorporated three 2.1.3 Television InfraRed Operational Satellite Teledyne Judson Technologies’ wavelength channels (TIROS) Series: Teledyne Judson Technologies (3-4µm, 4-5µm, and 6-14µm). The detectors were developed and qualified IR Imager for the AVHRR cooled by a closed cycle cooler for operation instrument and IR Sounder for the HIRS instrument between 80°K and 90°K. The assembly includes for the TIROS series satellites [1] now called Polar three detectors in a single hermetically sealed Operational Environmental Satellite (POES). TJT housing with a narrow field of view and cold filters. delivered all the required TIROS HgCdTe sensors Short wavelength channels are InSb with a cooled over more than 10 years. We remain the qualified FET and reduced background while the long wave vendor for these assemblies. NOAA contributed channels use HgCdTe photoconductors. AVHRR and HIRS Instruments, with IR sensors 2.2.3 Sounding Atmospheric Broadband Emission delivered by Teledyne Judson Technologies for the Radiometry (SABER): Teledyne Judson Technologies European Meteorological Operational Satellite built both photovoltaic and photoconductive (METOP-1). infrared detectors for Sounding Atmospheric 2.1.4 Multi-function Transport SATellite (MTSAT) Broadband Emission Radiometry (SABER) Series Weather Satellite: For the Japanese weather instrument [3] [4], see Fig. 4. The SABER is on board satellite, Teledyne Judson Technologies supplied the Thermosphere, Ionosphere, Mesosphere, fully space-qualified HgCdTe infrared sensors for Energetic and Dynamics (TIMED) space craft. TJT Water Vapor band, and long wavelength detector developed IR sensor assembly which consists of 10 arrays for the multiple imaging bands. channels, including HgCdTe, InSb and InGaAs detectors, each with integral narrow band filter. The

75 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 InSb and InGaAs detectors are coupled to a cooled integral JFET as the 1st stage hybrid amplifies.

SABER was launched on December 7, 2001 and began operations on January 22, 2002. TIMED is in a 625 km circular orbit at an inclination angle of 74.0745°. SABER is one of four instruments on NASA's TIMED Mission. Its goal is to explore the Mesosphere and lower Thermosphere globally and achieve a major improvement in our understanding of the fundamental processes governing the Fig. 4: SABER mission is to explore the mesosphere energetic, chemistry, dynamics, and transport of the and lower thermosphere [5] atmospheric region extending from 60 km to 180 km. 2.3 Airborne Linear Detector Arrays in SABER's mission is to perform measurements of Midwave and Longwave Infrared: Over the past 20 temperature, ozone, carbon dioxide, water vapor years Teledyne Judson Technologies supplied custom and other trace gases to learn more about the designed InSb and HgCdTe linear array sensors for complex relation of energy transfer between the airborne remote sensing applications. The MODIS upper and lower atmosphere. Airborne Simulator (MAS) [8] is an airborne scanning spectrometer that acquires high spatial resolution 2.2.4 Solar Occultation For Ice Experiment imagery of cloud and surface features from a NASA (SOFIE): The Solar Occultation for Ice Experiment ER-2 high altitude research aircraft. The MAS (SOFIE) [6] is one of three instruments onboard the provides multispectral images for the purpose of Aernomy of Ice in the Mesosphere (AIM) Satellite. validating algorithms for remote sensing of clouds, SOFIE performs solar occultation measurements in aerosol, water vapor, and surface properties from 16 spectral bands that are used to retrieve vertical space. Nineteen (19) of the bands correspond to The profiles of temperature, O3, H2O, CO2, CH4, NO and Moderate Resolution Imaging Spectroradiometer polar mesospheric clouds (PMC) extinction at 11 (MODIS) that was developed as part of the Earth wavelengths. Teledyne Judson Technologies Observing System (EOS). Recently, Teledyne Judson supplied HgCdTe, Ge, and Si infrared sensors to Technologies successfully delivered to Enhanced cover 14 infrared spectral bands. MODIS Airborne Simulator (E-MAS) a midwave - 2.2.5 Atmospheric Chemistry Experiment (ACE): longwave IR linear detector array sensor assembly The Atmospheric Chemistry Experiment (ACE) [7] is with a special detector layout design for an airborne a Canadian Space Agency mission. The ACE mission remote sensing application. objective is to monitor and analyze the chemical 3. Teledyne Imaging Sensors contribution to processes that control the distribution of ozone in the Remote Sensing: Teledyne Imaging Sensors (TIS) has upper troposphere and stratosphere. A also been advancing the state-of-the-art technology in comprehensive set of simultaneous measurements of the area of Infrared detector for remote sensing. TIS trace gases, thin clouds, aerosols, and temperatures has extensive heritage in remote sensing and are being collected by solar occultation from low successfully delivered detector assemblies for both earth orbit, including detection of more than 30 astronomy & planetary and earth observing [9] [10], molecules such as O3, N2O, HNO3, H2O, HCl, Hf, NO, see Fig. 5. Table 2 summarizes TIS detectors utilized NO2, CO, CO2, CCl3F and N2O5. Teledyne Judson in major missions. Technologies supplied the InSb sensor for the mission. 76 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 for both cooled and un-cooled detectors. The detector packages are integrated with cold optics inside the detector package, including cold shield and cold filters. Multi-band spectral or hyperspectral remote sensing imaging can be realized by implementing multi-band spectral spatial filters in front of the FPA.

TJT has also been advancing the integrated dewar cooler assembly (IDCA) technology for airborne and Fig. 5: Teledyne Imaging Sensors selected remote space-borne remote sensing. The obvious advantage sensing programs of IDCA is that it integrates the cooler and detector 4. Future work on Advanced Sensor Technologies: sensor together in a compact volume size. A high With the IR sensor technology advancing, there is reliability, small size and low power consumption more demand for large coverage areas, high image IDCA is an attractive direction for both airborne and resolution and multispectral imaging, as well as fast spaceborne remote sensing. data rate and analysis in space borne remote sensing applications. 5. Conclusions: We have presented a brief overview of

Teledyne Judson Technologies and Teledyne Imaging To meet such demands, Teledyne Judson Technologies Sensors’ heritage detector arrays in remote sensing and Teledyne Imaging Sensors have developed 320 x applications developed over the past decades. These 256-30µm pitch and 1K x 1K-15µm pitch InGaAs focal detectors were produced in various spectral bands plane arrays [11,12], and are advancing the state-of- ranging from near infrared to mid-wave, and to long the-art for even smaller pixel larger format InGaAs wavelength band utilizing InGaAs, InSb and HgCdTe FPAs [13], as well as linear arrays for un-cooled SWIR materials. remote sensing. These new technologies can ultimately improve image resolution and image coverage, while With the high demand in remote sensing, Teledyne supporting analog and digital image data through continues to advance and lead in various new detector ROIC output. Teledyne has developed the most array technologies and detector assembly cutting edge technology for HgCdTe 640 x 512, 1K x development and implementation in airborne and 1K, 2K x 2K, and 4K x 4K pixel format SWIR, MWIR, space-borne remote sensing. and LWIR focal plane arrays. These products operate Acknowledgements: The authors are thankful to at 37K or higher temperatures. Some have been many Teledyne Judson Technologies colleagues for implemented in space-borne and airborne remote their support and assistance to this work. sensing imaging in recent years.

TJT has developed state-of-the-art hermetically sealed detector assembly techniques and products

77 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Table 2. Teledyne Imaging Sensors’ detectors utilized in major missions PROGRAM END USER YEAR LAUNCHED Hubble NICMOS NASA Launched 1990 Hubble WFC3 NASA Launched 2009 Hubble SM4 (ACS Repair) NASA Launched 2009 WISE NASA Launched 2009 Wide Field InfraRed Survey NASA In development (Launch TBD) Telescope (WFIRST) NPOESS/CRIS NOAA Space Qualified (Launch TBD)

GLORY NASA / GSFC Rocket failed on launch 2010

AURA (TE & IR FT Spectrometer)NASA Launched 2004 Deep Impact (IR Spectrograph) NASA Launched 2005 CIVA/Rosetta ESA Launched 2004 CONTOUR NASA Launched 2002 JWST (NGST) 1. NIRCam NASA Space Qualified (Target Launch 2018) 2. NIRSpec

LDCM TIRS NASA and USGS Space Qualified (Target Launch 2012)

GOES-R NESDIS Space Qualified (Target Launch 2015) Rocket failed on launched 2009/ OCO-R NASA Target re-launch 2013 MMM/Chandrayaan-1 NASA JPL/ISRO Launched 2008 J-MAPS NAVY Space Qualified (Target Launch 2013)

MRO (CRISM spectrometer) NASA Launched 2005 LEISA (New Horizons) NASA / GSFC Launched 2006

References radiometry (SABER) : sensor design, performance, and lessons learned”, Proc. SPIE [1] J.R. Frederick, J. Kimchi, T. Wong, “High Vol. 6297, 62970U (2006) Performance HgCdTe Photoconductive [5] GATS, Inc. Atmospheric Science, [online]. Detector Assemblies for Space Applications”, Available at: http://www.gats- Proc. SPIE Vol. 2812 (1996) inc.com/projects_saber.htm [2] NOAA Satellite and Information Service, Office [6] S. Hansen, A. Shumway, C. Fish, J. Peterson, P. of Satellite Operations, National Environmental Mace, J. Cook, J. Nelsen, D. Hooper, Q. Young, Satellite, Date and Information Service S. Wassom, J. Kemp, L. Gordley, M. Hervig, (NESDIS), [online]. Available at: http:// “SOFIE Instrument Model and Performance www.oso.noaa.gov /goesstatus/ Comparison, Proc. SPIE Vol. 6297 (2006) [3] J. Stauder, R. Esplin, L. Zollinger, M. Mlynczak, [7] M.A. Soucy, F. Chateauneuf, C. Deutsch, N. J. Russell III, L. Gordley, T. Marshall, “Stray Etienne, “ACE-FTS Instrument Detailed Light Analysis of the SABER Telescope”, Proc. Design”, Proc. SPIE 4814 (2002) SPIE Vol. 2553, (1995) [8] M. King, W.P. Menzel, P. Grant, J. Myers, G.T. [4] S. Brown, M. Jensen, S. Jensen, G. Hansen, L. Arnold, S. Platnick, L. Gumley, S. Tsay, C. Zollinger, R. Esplin, J. B. Miller, “Sounding of Moeller, M., Fitzgerald, K. Brown, F. the atmosphere using broadband emission Osterwisch, “Airborne Scanning Spectrometer 78 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 for Remote Sensing of Cloud, Aerosol, Water imaging technologies for x-ray, UV, visible and Vapor, and Surface Properties”, American near infrared”, Proc. SPIE Vol. 7021 (2008) Meteorological Society (1996) [11] H. Yuan, G. Apgar, J. Kim, J. Laquindanum, [9] R. Blank, S. Anglin, J. Beletic, Y. Bai, S. Buck, S. V. Nalavade, P. Beer, J. Kimchi, T. Wong, “FPA Bhargava, J. Chen, D. Cooper, M. Eads, M. Development: from InGaAs, InSb, to HgCdTe”, Farris, D. Hall, K. Hodapp, W. Lavelle, M. Proc. SPIE Vol. 6940, 69403C (2008) Loose, G. Luppino, E. Piquette, R. Ricardo, T. [12] H.Yuan, J. Kim, J. Kimchi, J. Bajaj, G. Ding, J. Sprafke, B. Starr, M. Xu, M. Zandian, “The Hwang, D. Lee, W.E. Tennant, “Development of HxRG Family of High Performance Image Large Format InGaAs 2D Photodetector Arrays Sensors for Astronomy”, Astronomical Society with Very Small Pixels”, 2010 meetings of MSS, of the Pacific Conference Series, Volume 437, Special groups on Detector Materials, February Solar Polarization 6, edited by J.R. Kuhn, S.V. 22-26, 2010 Berdyugina, D.M. Harrington, S. Keil, H. Lin, T. [13] H. Yuan, J. Kimchi, L.C. Kilmer, J.T. Getty, E. Rimmele, and J.T. Buino. R. Glaretas, “Recent Progress in Developing [10] Y. Bai, J. Bajaj, J. Beletic, M. Farris, A. Joshi, S. Very Small Pixel InGaAs 2D Photodetector Lauxtermann, A. Petersen, G. Williams, Arrays at TJT”, 2011 meetings of MSS, Special “Teledyne Imaging Sensors: Silicon CMOS groups on Detector Materials, February 28- March 4, 2011.

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80 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

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82 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Remote Sensing Payload Hardware: Microwave Sensors

Industry Role in ISRO’s Microwave Remote Sensing Payloads Nilesh M. Desai Space Applications Centre, ISRO, Ahmedabad [email protected]

1. Introduction: Under the Microwave Remote industries in helping MRSA address the challenges of Sensing Programme (MRSP), Microwave Remote microwave SAR and other payload realization. Sensors Area (MRSA/SAC/ISRO) has been involved 2. Recent Missions involving Microwave Sensors: in developing and enhancing the capabilities of Table-1 gives the major mission parameters of ISRO’s Earth Observation (EO) missions involving microwave sensors for which development activities microwave sensors. Subsequent to the launch of a were completed recently with industry participation. Multi frequency Scanning Microwave Radiometer Airborne and Spaceborne SARs are basically imaging (MSMR) payload onboard Oceansat-1 (IRS-P4) in sensors with numerous land and ocean applications. 1999, payload developmental activities related to four Scatterometer is utilized for local/global wind vector major EO missions involving microwave sensors viz. retrieval over the ocean while radiometers estimate Radar Imaging Satellite (RISAT-1) Synthetic Aperture and monitor a number of geo-physical atmospheric Radar (SAR), C-band Airborne SAR for Disaster and ocean parameters like water vapour content, Management (DMSAR), Oceansat-2 Ku-band Pencil rainfall, cloud cover etc., which are important for beam Scatterometer and passive imaging radiometer global weather forecasting and climate studies. (MADRAS) for Megha-Tropiques (MT) have been completed in the last decade. RISAT-1 satellite, scheduled for launch in 2011-12,

consists of an active antenna based C-band One major feature of these developments is that the multimode, multi-polarisation SAR, having Stripmap, hardware for these microwave sensors have been ScanSAR, Spotlight and Sliding Spotlight SAR modes developed with core radar electronics concept. The [1][2]. The Ku-band Pencil beam Scanning other important feature is the participation and Scatterometer payload onboard Oceansat-II has been involvement of the local indigenous and a few foreign successfully launched in 2009 and is currently industries in realization of portions of various new operational [3]. and challenging technology elements of these Megha-Tropiques (MT) mission, a significant payloads, based on MRSA provided designs. collaborative science project between ISRO, India and Moreover, all the planned follow-on and near-future CNES, France, carries Microwave Analysis and microwave sensors are also envisaged to follow a Detection of Rain and Atmospheric Structures similar approach of core radar electronics and (MADRAS) imaging radiometer, and is scheduled for industry participation. The sections below describe launch in 2011. ISRO’s C-band Airborne SAR has the role played by mostly local and a few foreign been replaced with an airborne SAR for Disaster Management (DMSAR).

83 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Table-1: Major Specifications of ISRO’s recent missions involving Microwave Sensors

MEGHA- OCEANSAT-II PARAMETER DMSAR RISAT-1 SAR TROP. SCATTEROMETER MADRAS Frequency 5.35 GHz 5.35 GHz 13.5 GHz 18.7-157 GHz

Platform B-200 aircraft IRS bus IRS bus IRS bus

Altitude 8 km 610 km 720 km 865 km Platform Velocity 120 m/s. (Nom.) 7.5 km/s. 7.46 km/s. 7.417 km/s. Off Nadir Look 65° to 85° 9° to 47° 43.6°, 49.0° 45° (Scanning) Angle Swath Coverage 6-75 km. 10-240 km 1450-1800 km. 1700 km. Resolution 2-10 m x 2-50 m. x 2 m/s (wind speed) 0.5-2°K (Temp.) (Range x 2-10 m. 2-50 m. 20° rms (dir.) 6-40 km Azimuth)

For RISAT-1 SAR, various flight model subsystems Check-Out units for all payloads, Quick look and like active antenna and tile electronics consisting of Near-Real Time SAR digital processors for DMSAR about 300 miniaturized MMIC based and RISAT-1 SAR [9][10][11] etc. have also been Transmit/Receive RF Modules (TRM) and ASIC based realized with the involvement of private and public TR Control (TRC) units along with onboard central sector industries. electronics like I/Q Digitizers based Data acquisition Table-2 gives an overview of industries and their and Signal Processing system (DAS), Digital Chirp contributions in fabrication of RISAT-1 SAR and other Generator (DCG), Radar Payload Controller (PLC), microwave payloads related subsystems and Frequency Generator (FG) and Receiver (RX) units, components in the last decade. Most of these high-end have been designed, fabricated and qualified. One technology developments were possible only with major feature of these developments is that the active industry participation and close interface. The hardware for RISAT-1 SAR has been standardized. success of the industrial development of new design Standardization of the hardware has enabled industry elements was possible because of the emphasis on the participation in design and production of these following aspects: hardware modules.

3. Industry Role in Microwave Payload • Vendors were selected carefully after analyzing Development: The major striking feature is that technical competence of the managers/personnel Payload development involves local indigenous and their willing attitude towards developing risky industries in a substantial manner in their realization. new technologies. The proof-of-the concept and Flight Models of various • Partnership approach was adopted in which in- new and challenging technology elements for RISAT-1 house capabilities both in terms of human SAR have been realized with the active participation resources and facilities were provided to industry and collaboration of local and indigenous public and partners to fill up the gaps. private sector industries. • Educating the vendors with ISRO’s quality approach with practical demonstration, process Indigenous MMIC fabrication line has been qualified and human resource qualification and constant at GAETEC foundry. The developmental models of guidance in quality audit. onboard baseband subsystems, Electronic Ground Support Equipment (EGSE) elements like Ground

84 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 • The necessary laboratories, clean rooms and other • Fig-1 gives the photographs of the various environmental facilities have also been set-up and standardized subsystems and support equipments operationalised at many of these industries. & facilities developed by industries for microwave payloads.

Fig. -1: Contributions of Industries in microwave missions

Table-2: Details of space hardware developed by industries for Microwave Payloads

Industry Hardware Contribution in last decade GAETEC, 7 types of MMICS Hyderabad ASTRA TR Module, TRC, RF Power Distr. NW , Power amplifier modules, High power Microwaves, SPST switches, Integration Blocks, Etching of Antenna Hyderabad Solectron Centum, Power Conditioning and Processing Unit (PCPU), Transmit-Receive Controller Bangalore (TRC), EPC for Tile Control Unit (TCU), TCU, Harness BEL, Ghaziabad Power amplifier module Agilent, TR module characterization System Hyderabad Bryka / Aeroflex Onboard Controller ASICs for Tile Electronics 85 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 & CG-Corel, Blr. Ambimat, DVM fabrication & testing Ahmedabad Trident Infosol, GCU Bangalore Data Patterns, GCU Chennai Advancetech, GCU Chassis (EGSE) Vadodara SLT, Gandhinagar Antenna Fabrication, Assembly & Alignment Of Antenna Layers Komoline, GCU Ahmedabad Circuit Systems, Antenna PCB (1m x 0.33 m) & Other PCBS-MLBs Gandhinagar CMC, Hyderabad Digital subsystems for Design Verification Models Bombay Machines, 3-Axis Scanner for Near Field Measurement Bangalore

4. Development Strategy for Follow-on & Future acknowledge the contributions of all their colleagues Microwave Missions: RISAT-1 follow-on mission in MRSA, Scientist/Engineers and other staff will carry a L-band Multi-polarization SAR [4] members of SAC/ISRO and other ISRO centres, who operating in stripmap mode and will mainly cater to are involved in the developmental activities related to applications related to agriculture and soil moisture Microwave Remote Sensors. analysis. In consonance with various application requirements and projections, ISRO has also planned References [1] “SAR Payload of Radar Imaging Satellite (RISAT) a number of other missions involving microwave of ISRO”, by Tapan Misra, S.S.Rana, V.H.Bora, N. M. sensors [5] for LEO orbits. The digital and RF Desai , C.V.N.Rao and Rajeev Jyoti, 6th Europ. Conf. subsystems are being upgraded, miniaturized and re- on SAR, EUSAR-2006, 16-18 May, 2006, Dresden, designed to meet the challenges of these follow-on Germany. microwave missions. Industries will have [2] “Advanced Digital Technology elements of opportunity in development and realization of these Synthetic Aperture Radar Payload of RISAT”, by microwave payloads. Nilesh M. Desai , J.G.Vachhani, B. Saravana Kumar,

th 5. Conclusion: This paper describes the challenges in V.R.Gujraty and S.S.Rana, 6 European Conf. on SAR, the involvement of industry in spaceborne microwave EUSAR-06, 16-18 May-06, Dresden, Germany. remote sensing infrastructure development in the [3] “Digital Receiver with FPGA based Signal country. Processor for ISRO’s Oceansat-II Scatterometer”, by N. M. Desai, B.SaravanaKumar, S. Gangele, Acknowledgements: The author would like to thank R.Agrawal, J.G.Vachhani and V.R.Gujraty Dr. R.R.Navalgund (Director, SAC), Shri A.S.Kiran International Radar Symposium, IRSI-2007, 10-13 Kumar (Associate Director), Shri S.S.Rana and Shri Dec., 2007, Bangalore.

V.R.Gujraty (Ex-DDs, MRSA) and Shri Tapan Misra [4] “Advanced Onboard Technologies for ISRO’s (DD/MRSA) and Shri R.K.Arora (DD-ESSA) for their RISAT-1 Follow-On L-Band Polarimetric SAR guidance and active encouragement to industry Mission” by N.M. Desai, B.Saravana Kumar, th participation in Microwave sensors related J.G.Vachhani, V.R.Gujraty and S.S.Rana, 7 Euro. developmental activities. The author also wishes to 86 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Conf. on SAR, EUSAR-08, 2-5 June-2008, J.G.Vachhani, Rinku Agrawal, CVN Rao, V.R.Gujraty Friedrichshafen, Germany. & S.S.Rana, 5th Asia-Pac. SPIE Intl. Remote Sensing [5] “A novel digital receiver concept for ISRO’s Conf., 13-17 Nov, 2006, Panaji, Goa. future Remote Sensing Radars”, by Nilesh Desai,

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deadline for inclusion in the next issue on “Atmospheric & Oceanic Remote Sensing” is Sept 20, 2011. - Editorial Team

87 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Real-Time Spectrum Analysis Reveals Time Domain Characteristics of Microwave Signals Thomas Hill, Tektronix, Inc. P.O. Box 500, M/S 50-317, Beaverton, OR 97077, USA [email protected]

1. Introduction: Spectrum Analyzer technology If interference is being experienced in an RF and design has changed as techniques for environment and the analysis tools used to discover microwave transmission have become time- the interference do not have the capability of varying, and as advancements in microwave triggering on transient RF, or cannot distinguish measurement technology have become available. between signals that occupy the same frequencies at The earliest form of microwave analyzer was a different times on a short-time transient basis, then manually tuned filter and detector combination the interference cannot be discovered. which simply indicated the signal level at the 2.2 Capturing these Problems for Analysis: Simply frequency to which it was tuned. A wave meter discovering the existence of a time-varying or is the simplest example of this. transient signal is not sufficient. Such signals must The introduction of electrically tuned signal be reliably captured to allow for further analysis. conversion circuitry created the swept-tuned There is a need to trigger on the time-varying microwave analyzer. A CRT was used to display frequency nature of modern microwave signals and the amplitude of all incoming signals as vertical the interference they may be subject to, or may even deflection, with the frequencies spaced cause to other services. Traditional methods can horizontally. capture continuous time segments of a signal, but Analog-to-Digital converters, along with Digital these recordings may or may not contain the time- Signal Processing, (DSP) are now used to capture varying transients if there is extended time between a much wider band of spectrum which may such events. The need is for a trigger that can use contain many signals simultaneously. Analysis is continuous time-transform processing without performed after the signals are captured. losing any of the incoming signal.

As time-varying signals have replaced the more 3. The Underlying Problem - Gaps in Analysis: traditional modulation forms, the Real-Time 3.1 Swept Analysis can’t see Time-Varying Signals: Spectrum Analyzer (RTSA) was developed to Swept frequency analysis inherently only detect the show these time-variations and separate multiple total power contained within the bandwidth of the time-varying signals overlapping in frequency. detector, as this detector is slowly swept across the 2. The Need: frequency band of interest. The detector is tuned to only one frequency at a time. It is blind to all other 2.1 Discovery of Problem Signals: When the need frequencies at that time. Therefore, as the detector is to characterise a microwave signal that sweeps, such an analyzer will miss transient signals contains transient time-varying events, or of duration less than the entire recurrent sweep time. characterise a signal where it is unknown if the There are gaps in the time that any one frequency signal contains such time-variations, then the can be seen. These time gaps are almost as large as analysis of the RF spectrum must include a full the sweep time itself. amplitude representation of these transient signals. 3.2 Real Gaps in DSP: A Vector Signal analyzer (VSA) digitises an entire band of signals at once, and

Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 examines these frequencies with a Discrete Time “Effective Gaps” created in the incoming signal. Transform (such as an FFT.) However, during the The proper functioning of an FFT requires that a display of Microwave Spectrum, the time gap filter be applied to the time samples before they between one FFT and the next is usually the same as are passed to the FFT process. This time filter the length of time that the display requires between reduces the samples near the beginning and near display updates. These time gaps between FFT the end of the time record to zero value. An processes, as seen in Fig. 1, are real gaps with example of such a filter is in Fig. 3. complete loss of the signal being analysed. If the DFT process repeats less often than the time occupied by one frame of input data, then there are inherently gaps in the coverage of the incoming signals. Such a situation is depicted in Fig. 2. The upper trace is the incoming signal which has an unexpected anomaly, of duration less than one DFT frame, within the left half of the drawing. Fig. 3: Time-window to be applied before the

FFT. The lower traces represent the time-windowed samples delivered to the DFT process. The anomaly Given that this filter is applied to all FFT of interest happens to fall in the gap between two processes, the result creates the “Effective Gaps” DFT frames. If the frame repetition rate were less where the end samples of one FFT record are often, the probability of intercepting this signal adjacent to the beginning samples of the would be proportionately less. subsequent FFT. An example of how this leaves parts of the incoming without analysis is seen in Fig. 4.

Fig. 4: FFT processes immediately following one Fig. 1: Gap between FFT frames due to compute another. time. These “Effective Gaps” also cause complete loss of the incoming signal. There must be no gaps at all if the small transient signal is to be discovered, or is to trigger a capture for further analysis.

3.4. The need for Triggering on specific Frequencies: Fig. 2: Real Gaps between FFT frames. While many VSAs can capture continuous signal data for extended periods of time, they can not be 3.3 Effective Gaps in DSP: Even if there are assured of the pre-determined capture of a specific contiguous and continuous FFT processes one frequency event. A signal that varies on both immediately after the other, there will be frequency and time, or even more importantly, 89

Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 multiple such signals that overlap, requires analyzed within the active portion of at least one triggering that is frequency selective and FFR frame. amplitude selective at the same time. This includes circumstances where a signal of greater or lesser frequency (regardless of amplitude) will not cause a false trigger. There are also circumstances where a signal that meets these criteria, but is lesser or greater amplitude at the same frequency also does not cause a false trigger. Fig. 5: FFT processes overlapping one another by 50%. 4. The Solution 5. Results 4.1. Digital Signal Processing Without Gaps: 5.1. Display of Time-Varying Signals: With FFT Advances in FPGA processing power now allow processes always overlapping at least 50%, an simultaneous parallel processing of multiple FFT analyser has been built that is capable of acquiring or Chirp-Z time transforms. 110 MHz of bandwidth and processing more than To meet the requirement of no gaps in the analysis of 292,000 spectra every second without missing any the incoming signal, the FFT processes must overlap data. To view this many spectra, they must be by at least 50% from one to the next. This is compressed so that the display, and even the human illustrated in Fig. 5. Here it can be seen that even the eye, can see the result of every one of the spectra. small transient frequency disturbance will always be

Fig. 6: The Bitmap compression process.

One method of compression is shown in Fig. 6. Each But here, the access point, with nearly spectrum is made into a bitmap as if it were to be continuous transmission is seen as dark, but the sent to the display. These bitmaps are accumulated nearby laptop has much stronger, but less into one bitmap by adding the number of times a frequent signal on the same channel. The bitmap pixel contains spectrum data. When the Bluetooth, with its 4 sets of 4 carriers each, is display is available for an update, the combined overlapping with the aforementioned WiFi, and bitmap is converted into colours or intensities that also overlapping the WiFi channel just one lower represent the number of times a pixel was “hit”. This frequency than the first one. display now shows the time-varying nature of the incoming signal. Even if the signal has a transient 5.2. Triggering on specific Frequency & spectrum that occurred only once, this will be shown Amplitude: Another capability provided by real- on the display. time FFT processing is the triggering of Fig. 7 is a display of multiple microwave signals in measurement processes based on events in the the same spectrum. There are three WiFi signals and frequency domain as well as time domain. Prior a Bluetooth with overlapping spectra. Ordinary to the development of real-time processing, a spectrum analysis can only see the strongest signal trigger could be generated only if the detected at any one frequency. power changed. If the FFT is processed at least as 90

Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 fast as the incoming data from the A/D above their current amplitude. This frequency converter, then the output of the sequential FFTs mask triggers on events at specific frequencies can be compared to a frequency "mask" even amongst other, much larger signals. representing the particular signal of interest. 5.3. Triggering using the Histogram Display: The Then when the FFT output matches the mask, a Histogram display now also provides a method trigger is generated immediately. Overlapping to draw a “Trigger Box” on the display. This box the FFTs removes the same effective gaps that allows triggering on the time-density of signals. result from the spectrum windowing as was the In Fig. 9 the box can read out the percentage of case for the histogram display. time that a signal is within the box. This can now trigger on this percentage, providing triggering on a “signal within a signal”. This is a true trigger on the time-varying nature of the signal, or of interference to a signal.

5.4. Analysis of Time-Varying Signals: Using the multiple continuous overlapping FFT processes, multiple overlapping signals can be

Fig. 7: Multiple Signals sharing the same spectrum. distinguished. Fig. 10 has one wide chirp signal, with two overlapping smaller chirps inside it. There are also several pulsed signals. Again, FFT processes with gaps can only see the strongest signal outline, and may miss several signals altogether.

Fig. 8: Frequency “Mask” triggered by one small Signal

The frequency mask can be drawn as another trace on the spectrum display. The internal numerical representation of this mask is compared to each of the DFT results as they are generated from the incoming signal data. If any Fig. 9: Histogram Trigger “Box” X location of the DFT has a Y-value which exceeds the Y-value of the corresponding X location of the mask, a trigger is generated. Fig. 8 has a display representative of the frequency mask. The spectrum has nine RF signals across the spectrum of interest. A mask has been drawn between two of these legitimate signals. Any signal that appears in this mask will generate a trigger even if it is 33 dB below the large signals. As this mask is drawn, the large signals will not generate a trigger even if they increase 3 dB Fig. 10: Multiple signals overlapping each other. 91

Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 5.5. Probability of Intercept: Guaranteed triggering on short transient signals is met by the overlapping 6. Conclusion: Spectrum analysis of Microwave of FFTs. The minimum length of a burst that will be signals can no longer ignore time variations of the triggered at full amplitude is calculated as an signals. Parallel DSP processes operating in real-time example of a practical application for triggering an are required to trigger or analyse signals without RTSA with 110 MHz bandwidth: introducing gaps. • Decimated sample rate of 150 MHz, = 6.67 ns per sample. Acknowledgements: The author wishes to • Triggering uses FFT frame = 1024 points = 6.83 acknowledge the assistance provided by Shigetsune μs. Torin and Marcus DaSilva in the preparation of this • 50% overlap is 1.5 frames = 10.24 us minimum paper. burst length. The display of a transient signal at full amplitude References also requires that at least one complete FFT frame [1] "Fundamentals of Digital Phosphor TM must intersect the signal burst. A calculation for the Technology in Real-Time Spectrum Analyzers" histogram display of an RTSA with 110 MHz Tektronix, Inc. application note. bandwidth: [2] T. C. Hill, “Real-Time Spectrum Analysis Reveals • Histogram CZT = 523 points = 3.49 us. Time Domain Characteristics of Frequency • CZT process time of 20.48 μs forces gaps. Domain Signals”, Automatic RF Techniques • 3.49 μs + 20.48 us = 23.97 μs min. burst length. Group (ARFTG) Conference, December 2008.

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92 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Digital Radar Receiver System (DRRS) A case study from Mistral Solutions Pvt. Ltd. 1. Introduction: The organization is a center for hardware abstraction layer. The system, based on vehicle research and control. It is equipped with VPX technology was modular in nature with a Telemetry, Tracking, and multiple other facilities capability of being upgradable with advancement in essential for control of the sub-systems. The center technology. COTS components were considered in has various ground systems in place which enable realizing the system with the application being them to track vehicles. As a technology development developed by the customer's in-house team. initiative, the customer has launched a program to Based on the specification provided by the customer, upgrade their radar receivers with newer technology the Mistral team proposed a hardware and software to enhance their tracking capability. This technology solution using a combination of COTS products also needed to ensure that future advancements in the available from our various partners. The following technology could be implemented through modular are the COTS modules and software tools that were up-gradation, with little or no change to the basic chosen for the system. infrastructure. The single board computers were based on PPC8641D 2. The Requirement: The customer saw a and built around the new VITA46 technology with demonstration of a Radar Receiver solution the capability to deliver up to 16 GFLOPS. It also has developed by Mistral and contracted Mistral to provision for module insertion which allows the card provide a custom solution to meet their requirements. to realize sensor interfaces. This is implemented in a The customer has installations of Radars, but the modular manner to ensure that an enhancement to back-end receivers and signal processing systems had the overall system can be implemented by changing little or no dynamic computing capability. This is a the modules. feature of the radar receivers (Radar Signal Processing) that is currently actively sought, to The Radar Receiver (Fig. 1) was implemented with provide a wider range of operations. three IF modules mounted on the base of the two single board computer cards. The IF Modules enable The industry has seen newer technologies emerge, the implementation of logic IP Cores like a “Digital like the new VITA 46 standard, which enables a Down Convertor” as well as any other mathematical multi-processor based computing environment with a models like Filters, Pulse compression, Fast Fourier capability to have high-speed inter-processor Transforms and more. communication as well as Processor to I/O communication. It was an automatic choice for the This combination allows the whole system to work as customer to narrow down on a Radar Processing high-end and modular Radar Receiver, a system System comprising of Digital Signal Processing which receives radar inputs, decimate the digitized hardware and Intermediate Frequency (IF) modules sensor information to the bandwidth of interest, which were based on the newer technology. apply mathematical models to extract target information and also store the scenarios through a 3. Solution Provided: Mistral provided a solution high speed storage media Interface with a fibre that was built in a modular structure with a Software channel module. Development Environment that would ensure that the customer could focus on the application implementation rather than at the driver or the

Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

Fig. 1: Radar Receiver • Digital Down Convertor core in the FPGA of the IF module, The chosen RTOS for the application – VxWorks, was • Low latency deterministic Communication an automatic choice considering the time critical between various nodes using the IPC library. operations. VxWorks ensures a hard real-time performance and thereby a time deterministic 4. The Challenges application implementation. • The specification provided by the customer were generic and we had to provide the customer with multiple iterations of application demonstrations, and thereby establish that the specification of our proposed cards as well as our services would meet their requirement • Integration of various cards as well as establishing the interoperability to operate on the same platform was a challenge. This involved porting of module drivers from earlier versions to the newer versions of the

Real Time Operating System, as well as other Additional software tools provided for the SBC Board Support Packages include: • Development of complex test cases to demonstrate the capabilities in-line with the • Signal processing algorithms using the Vector actual application signal processing libraries • Sourcing and integrating the components Profiling of processor cycles and event analysis to • from different vendors and providing support assist rapid prototyping and application for these components to the customer with implementation through Profiling and debugging Mistral being the single point of contact. tools

• Implementation of logic blocks through the 5. Key Achievements Firmware Development Kit for the IF module • System Implementation with the new VPX with Virtex5 FPGA technology

94 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 • A Multi-Channel receiver (12 IF Channels) • End-to-end system, enabling the customer to implementation focus on the application implementation • Design and Validation of complex • A modular approach with the capability to mathematical models before implementation scale the computing elements for future • Implementation of the mathematical and requirements compute intensive models in the final system • Platform which can be used even in the event • Validation of Time Correlated Algorithm of the front-end receivers undergoing an up- execution gradation • Winning the customer’s confidence with the • Platform with the capability of handling a new technology. change even if the Radar elements were upgraded

• Got Mistral as the system integrator, who has 6. Customer Benefits the ability to provide end-to-end services for a quick execution from concept-to-deployment. • A High-end Radar receiver solution based on up-to-date technology

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Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

96 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Contributions of K.V. Microwave Materials, Ideal K.V. Microwave Products & Sahajanand Laser Technology to RS Activities Dr. Kanhiya Lal, Executive Director RF & Microwave Division, Sahajanand Laser Technology Ltd. [email protected]

During this period (1978-till date), we contributed in Tapan Mishra et.al. was also published in “IEEE Trans the following remote sensing activities: on Geosciences and Remote Sensing” Vol. 1. Black Body Target (BBT) For Ground Calibration 40,No.2,pp504-508,2002 on the subject. of Multi-frequency Scanning Microwave Radiometer (MSMR): MSMR and Ocean Colour 2. Planar Near Failed (PNF) Anechoic Chamber for Monitor (OCM) were the two payloads that were Space Antennas Characterization: KVMM assigned flown on board Ocean set-I (IRS-P4) on May 26 1999 job to design supply and installation of Microwave from SHAR, ISRO. Two BBTs were designed and absorber in the PNF range and its validation. Design developed by KVMM for ground calibration of the parameters of the PNF range were: MSMR. These BBTs were designed with a goal of achieving very high emissivity (≥ .999) which 1. Size of PNF: 12.65x10mx11.5m. corresponds to very high reflection loss/absorbance 2. Scanner a) Make M/S Orbit FR – Israel; b) Type: in the operating frequencies of 6.6, 10.65, 18, and A-1-4953-1-9m-6m-v; c) Scan Area: 9mx6m. 21GHz having low thermal gradient from top to 3. Antenna Positioner: Supplied and Installed by bottom. Prior to full scale model, a scaled down SAC which includes Mounting Bracket Metal model was made by KVMM with required tower, azimuth positioner and Z axis slide. measurement test bed. To achieve this, absorbing 4. Back-Up Structure Construction: By SAC. material (coating) was tested in thermovac condition 5. Quiet –Zone Volume: 9m×6m×3m (L×H×W). for TML, CVCM, Thermal Diffusivity, Specific Heat, 6. Quiet –Zone Performance: -40 dB throughout at Thermal Conductivity, Sample Density and Return frequencies ≥ 2.0 GHz. Loss over the full operating range. The scaled down The room reflectivity, which is one of the 18 error model of the BBT comprising 3x3 absorbing material sources in PNF range and directly related to KVMM coated pyramids was tested by return loss maximum scope of supply, was evaluated by free space VSWR and minima method. Subsequently, as further method. The worst value of room reflectivity at confirmation the emissivity of BBT was tested at various locations / heights of PNF range was found Defence Lab, Jodhpur. The emissivity of the BBT to be -53.3 dB, -61.6 dB and -57.6 dB at 2.0, 5.0 and 8.0 Sample was better than the designated value of 0.999 /11.0 GHz, respectively against the designated at all frequencies. The thermal gradient test on the performance of -40.00 dB. sample was also carried out. Based on the above, 3 full scale BBTs (One Earth Antennas tested in the PNF range were used in Target, One Sky Target-1 for 6.6 GHz and 10.65 GHz MSMR, Ku band scatterometer and Radar Imaging and One Sky Target-2 for 18 and 21 GHz) were Satellites. successfully developed whose performance met the 3. Movable PNF Range: As Ideal K.V. Microwave specification laid down by MSMR Project. Products PVT Ltd, We supplied absorbers for movable Planar Near Field Range under clean room An article entitled “Ground Calibration of Multi conditions were supplied to test antennas for Radar frequency scanning Microwave Radiometer” by Imaging Satellites.

Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 • Size of PCB up to 0.4 mtr x 1.2mtr (can be 4. CNC Base Electro-Mech. Multifunction Machine made for 1mtr x 1mtr) For Multi Layer Patch Antenna: CNC base Multifunction Machine is one of the Special Purpose 5. Design & Development of Scaled Down QM of Machine designed & manufactured for Fabrication / Black Body Source For On Board Radiometer Assembly of the Multilayer Patch Antenna for Calibration: From Jan. 2007 all the activities started at different application by SLTL. KVMM were shifted to Sahajanand Laser Tech. Ltd. Features: E- 30, Electronics Estate, Sector-26 GIDC, • Clean room facility. Gandhinagar (SLTL) (Gujarat) • Alignment of the Duroid /dielectric substrate PCB with accuracy. From SLTL we participated in design and • Resolution /Repeatability of 10µm. development of QM of BBT for on board calibration • Inspection of the RT Duroid / any dielectric of Millimeter Wave Sounder Project. The BBT had to substrate PCB at high magnification CCD be space qualified including vibration and thermal vision system with cycling. In addition to the specification of BBT for • 120x which is in-house design ground calibration we have successfully completed • Pick& Place using Vacuum (80 to 210 milibar) the QM of BBT with following deliverables. used for gripping of substrate. • Measure Planarity of Substrate by Point Laser. 1. Black Body Source • High Speed drilling at 60000 RPM on RT 2. Mobile Target Duroid at Carbon Fiber Reinforced Plastic. 3. Track • Software control the whole automation of the 4. Control Panel and Machine like Positioning, Alignments, 5. Tx/Rx feed system with interface. • Inspection Planarity Measurements High speed drilling and Pick &place of the different substrates.

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Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Measuring the Quality of Chirp Radar Pulses using Impulse Response (Time-Sidelobe) Thomas Hill RF Products (RTSA), Tektronix, Inc. Beaverton, OR 97006 USA

1. Basic Radar Chirp Measurements: Modern Radars a forward transfer measurement. The Network often use one form or another of “Compressed Analyzer supplies the swept RF stimulus in addition Pulses”. Such a pulse is actually a modulated pulse, to measuring the resultant output signal. A which can be compressed in the Radar receiver signal measurement of the quality of a complete radar processing. One common form of compressed pulse is transmitter can be made using the FM chirp from the a Linear FM chirp. (LFM) Traditional measurement of radar's own exciter as the swept RF source. In this the quality of a linear FM chirp has used Frequency manner, the quality of the generated chirp as well as linearity or Phase Linearity. The linearity of frequency all modules that the chirp passes through will be or phase of the chirp tells only part of the story. If a tested together as a complete assembled radar. reflection, as in Fig. 1, or other time-related mechanism results in a delayed copy of the intended pulse (a secondary pulse) added to the main pulse, the linearity measurements may not easily discover the problem. This type of distortion or error in a transmitted pulse does not exhibit changes in linearity across the time of the pulse. If a chirp pulse has periodic incidental modulation (particularly amplitude modulation), such an error may also very difficult to determine. The frequency or phase linearity measurements are not able to measure changes which are restricted to variations in pulse Fig. 2. One example of a reflection. amplitude.

The most obvious measurement is of a reflected and delayed copy of a chirp included with the main pulse. Such a secondary pulse can be simultaneously measured for both time delay and relative amplitude by plotting the impulse response of the main chirp pulse. This is functionally equivalent to a TDR using the chirp itself as the excitation signal.

Fig. 1. One example of a reflection. Another defect, which this process can easily discover and measure, is incidental periodic Therefore a time-domain measurement is required to modulation. Incidental modulation adds sidebands discover and quantify such chirp pulse errors. to the sweeping RF carrier. These sidebands effectively create lower amplitude copies of the chirp 2.. A Time-Domain Measurement: Impulse that appear as pulses both preceding and delayed Response has commonly been included in the behind the main chirp as shown in Fig. 3. All of these measurements made by vector network analyzers. As defects would appear as false responses in a radar such, it is performed on components or assemblies as receiver. 100

Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 The multiplication de-chirps the acquired pulse. After dechirping, the Inverse Frequency Transform is performed to transform the result back into the time domain. This is now the traditional Impulse Response of the incoming chirp signal which passed through the radar system [1].

B. IPR Results for a reflection meassurement. In Fig. 5 the amplitude measurement result shows the secondary pulse (time sidelobe) as 42.40 dB below the main pulse (main lobe).

Fig. 3. One example of a reflection.

3. The Impulse Response Measurement: A powerful measurement of these defects is the Impulse Response Measurement (IPR). It is also called a Time- Sidelobe measurement, as it shows a main lobe representing the main pulse, and in similar fashion to a spectrum plot for a frequency domain measurement, the IPR shows smaller lobes for each time-delayed copy at the Fig. 4. Block Diagram of the IPR measurement including side of the main pulse. The name “Impulse Response” amplitude correction. comes from the mathematics of the measurement, which represents the output result from the network under test if it had been excited with an impulse. The name “Time Sidelobe” is more representative of the effect that such errors have in the Radar receiver.

A. The basic Impulse Response (IPR). The RF chirp is first digitized. The windowed set of time samples is then transformed into a frequency-domain spectrum. This can be accomplished by any of several Discrete Time Fig. 5. IPR with secondary delay of 47% of the Pulse Transform processes, including the Fast Fourier width. Transform (FFT). A reflected pulse will be displayed as one time sidelobe separated by twice the path delay from the This spectrum data is then multiplied by the complex main lobe. conjugate of a representation of an ideal chirp as was expected to have been transmitted. In a practical C. IPR measurements for other pulse defects: implementation of a measurement tool, this ideal Measurements which include a secondary reflected chirp can be mathematically estimated using the pulse are one use of this measure of quality. There are actual incoming signal, or it can be entered by the other pulse conditions that also can be measured equipment operator for increased measurement using this method. One example is a chirp pulse that accuracy. has incidental sinusoidal modulation.

101

Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 The relationship between the impulse sidelobe delay sides of the main lobe. A plot of frequency versus time time and the frequency components of the chirp is for a chirp will reveal only gross errors. The plot in given in (1). Fig. 7 shows no indication of the amplitude modulation sidebands present at all frequencies. It (1) also cannot show any amplitude variations Where ∆T is the time difference between the time themselves. sidelobes and the main lobe, Fm is the frequency of the incidental modulation, Td is the duration time of the chirp, and Fd is the frequency sweep width during the chirp. Such a pulse exhibits modulation sidebands on both sides of the carrier in the frequency domain. For a chirp pulse, this effectively has a secondary pulse both preceding and following the main pulse in the time domain.

D. IPR measurement time resolution: The time resolution in the measurement is determined by the Fig. 8. Plot of frequency error versus time. width of the main lobe of the impulse response. The lobe width is primarily the inverse of the frequency Fig. 8 is a more sensitive measure of frequency errors. width of the chirp. Additionally the required time There is still no indication of the amplitude window function will increase the lobe width [1] modulation sidebands. This measurement is produced by subtracting an ideal chirp waveform from the measured pulse, leaving only the errors from a perfectly linear chirp. This plot has been expanded revealing only the noise included in the measurement bandwidth.

Fig. 6. IPR measurement of chirp pulse with modulation sidebands. E. Comparison with traditional measures of chirp quality.

Fig. 9. Plot of phase versus time.

Phase is always a more sensitive measure than frequency. In Fig. 9 the phase also shows no indication

Fig. 7. Frequency vs. time plot. of the amplitude modulation. The sidebands due to The example displayed in Fig. 6 has a chirp width of the modulation are not visible. 100 MHz, time duration of 10 microseconds, and Phase error, shown in Fig. 10 is produced by incidental AM modulation at 15 MHz rate. This subtracting the ideal phase parabola from the results in time sidelobes at 1.5 microseconds on both measured phase. Even in this most sensitive 102 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 measurement, there is a long-term phase error seen FFT frame. This is approximately 13 microseconds. due to other errors, but no effect from the amplitude This cannot resolve the 1.5 microsecond delay time. modulation. The available frequency resolution is also insufficient. This limit comes from using the FFT without the time compression resulting from the impulse response mathematics.

Fig. 10. Plot of phase error versus time.

Fig. 13. Plot of phase error versus time.

A Time-Sidelobe plot of incidental Frequency Modulation at a 1 MHz rate is shown in Fig. 13. This lower modulation frequency is representative of possible power supply switcher modulating the chirp.

Fig. 11. Expanded plot of amplitude versus time. Only a plot of pulse amplitude versus time in Fig. 11 shows any indication of this low-level AM. Since the modulation is only a few dB above the broadband noise, it is difficult to measure the character of the modulation. It is unclear if this is a single-frequency sinusoid, or is largely noise.

Fig. 14. Plot of Frequency error versus time.

Again, the frequency error is not sensitive enough to see the modulation within the noise.

Fig. 12. Spectrogram of the chirp with modulation. Using a Spectrogram (Fig. 12, a set of FFT spectra over time placed one above the other to show time vertically, frequency horizontally, and amplitude as color or intensity) is limited by the FFT process. For the 110 MHz bandwidth used for these measurements, the available time resolution is one Fig. 15. Plot of phase error versus time. 103

Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 [1] Charles E. Cook & Marvin Bernfeld, “Radar The phase error is sensitive enough to see that this is Signals – An Introduction to Theory and FM and not AM. This is how the determination is Application”, 1993, Artech House. made, as the IPR plot shows only the sidelobes, it does [2] Walter G. Carrara et. al., “Spotlight Synthetic not show either they are AM or FM. Aperture Radar”, 1995, Artech House. These traditional measurements of chirp quality can [3] Alan Oppenheim & Ronald Schafer, “Discrete- be compared to the IPR results to demonstrate the Time Signal Processing”, 1989, Prentice-Hall. superiority of the impulse response measurement as a [4] T. C. Hill, “Measuring Modern Frequency measure of the quality of the linear FM radar chirp. Chirp Radars,” Microwave Journal Magazine, Vol 51, No. 8, August 2008. 4. Conclusion: Impulse Response is an improved [5] T. C. Hill & Shigetsune Torin, “Amplitude method of measuring the quality of FM chirp radar Correction for Impulse Response pulses. This can be implemented as a signal analyzer Measurement of Radar Pulses,” Unpublished. measurement utilizing the radar chirp itself as the swept frequency excitation signal.

References

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104 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 An Interview with Shri Malla Reddy, Managing Director, Astra Microwaves Products Limited, Hyderabad

Signatures: Shri Malla Reddy, at systems for prestigious programs like RISAT-1, the outset, ISRS-AC is thankful to Indian Remote Sensing Program and also for various you for sparing your time for this GSAT programs. We look forward to continuing our Interview. Could you tell us briefly relationship with ISRO and to deliver more products about your company, M/s. Astra for the upcoming programs at ISRO. Microwave Products Limited (AMPL) and nature of its activities? Signatures: AMPL has contributed significantly in MR: Thanks for the opportunity. development of Microwave and RF subsystems for ISRO’s It is my pleasure to interact with you. Astra Remote Sensing payloads and satellites. Will you throw Microwave Products Limited (AMPL) is a company some light on AMPL’s major accomplishments in this founded by three Microwave Engineering segment? Professionals in the year 1991. Today, we are a public MR: The first product delivered to SAC was an S- listed company with 700 + employees and a turnover Band 8x8 Switch Matrix for GSAT-4 wherein we had of 160 Crores. Since its inception, AMPL has focused delivered 2 FM and 1 Qualification model. Then, we on design, development, fabrication and testing of were involved in the development and fabrication of R.F. and Microwave Components & Subsystems that various RF Sub-systems like TR Modules, Power find application in Defense, Space, Distribution Networks and Antennas for C-Band Telecommunication and Meteorology. Our operations Synthetic Aperture Radar (SAR) payload of RISAT-1 are based out of Hyderabad and we operate from four project. During this, we have also carried out up- world class facilities, including one dedicated facility screening activity for RF devices. We also delivered a for Research and Development. An exclusive facility 4x4 switch matrix for the GSAT-7 project, X-Band for design and development of Space Components QPSK, S-Band QPSK and BPSK Transmitters as well and Subsystems has also been set up in the same as a number of other subsystems to ISAC. For VSSC, location. We are an ISO-9001 certified company and Thiruvananthapuram, we have carried out fabrication recently one of our special project divisions has been & assembly of various Power and control modules as certified to be compliant to AS9100 standard. The well as screening of active and passive components. facilities boast of state of the art infrastructure for Recently, L-Band TR Modules with 200 watt output assembly and test of RF and Microwave products are developed for MOTR project for SHAR. Today, including environment test facilities. This combined we are working on fabrication of Ku-Band Receivers with over 500 man years of relevant experience in RF for the GSAT Program and in the process of and Microwave domain for our key personnel has delivering V/UHF-Payload for GSAT-7. helped us to grow to be among the leaders in this segment with the ability to offer a one-stop solution Signatures: ISRO has been developing RF & Microwave for our customers. subsystems for its communication and remote sensing satellites since mid-1970s. Why did it take so long for a Signatures: AMPL is a major and dominant private private Indian industry like AMPL to be set up and reach player in India’s Aerospace sector. Will you share with us to its present maturity levels for effective contribution in some of your major achievements in last decade or so? ISRO’s programmes? MR: AMPL started interacting with the Aerospace MR: During initial years after establishment in 1991, Sector, especially ISRO starting from the year 2004. AMPL concentrated on development of RF and We have been working with various divisions of Microwave components/sub-systems for Telecom ISRO and are proud to have supplied our sub- and Defense. In 2001, AMPL participated in the 106 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jun 2011 Industry meet conducted by ISRO, which helped us towards the indigenous development of critical RF understand the needs of Space Industry. Accordingly, and Microwave Components and Subsystems. DRDO we invested in creating an exclusive facility for space was dependent on imports for such modules and thus segment. It was ready by 2003 after which it went we set out in the pursuit of creating a company that through various stages of qualification for the facility, could bring together skilled workforce along with the clean room and assembly line including test right infrastructure to develop these modules infrastructure. Certification of operators and indigenously. This was the main motivation for us in inspectors followed next. AMPL also took initiative in starting AMPL and today, with the support of DRDO qualifying vendors, both in India and abroad for and ISRO, we are able to meet some of the critical RF special activities. Getting into space business needs a and Microwave needs for advanced systems lot of investment to build up the facility and qualify it development within India. We are happy that we to meet the stringent reliability expectations. have been able to contribute towards self reliance of Production volumes are low and reliability the country and I hope that we would continue to expectations are very high. It took us more than 2 receive opportunities to work on cutting edge years to complete the qualification activities and thus technologies with DRDO and ISRO in making India a from 2006, we started executing orders for FM fully self reliant country in these fields. fabrication. ISRO slowly built confidence in our abilities and now we are getting opportunities to Signatures: What were the challenges involved in work with ISRO on critical sub-systems. realization and delivery of Transmit-receive Modules (TRM) for ISRO’s RISAT-1 Synthetic Aperture Radar Signatures: Today also, why are only very few and limited (SAR) Payload? private industry players involved in building RF & MR: Development of a Transmit-Receive module is Microwave subsystems? very critical as both transmit and receive chains with MR: Working for space requirements requires a lot of high gains have to be accommodated in a small commitment, patience, dedication and focus to meet housing. For this objective, AMPL proved the stringent reliability and quality requirements. High concept with a prototype using commercially investment and high lead time for realizing products available components. Taking inputs from each stage, is expected as no compromises are allowed due to the design and development of the final TR module mission critical nature of systems. This means that was carried out over six iterations. Thereafter, very few industries venture into this segment fabrication and testing of 701 TR modules was considering the long duration for getting business completed in reasonably less time. During returns. Our past experience in realizing MIL production, the total number of units fabricated by qualified products was one of the major factors that AMPL was 703 as against a requirement of 701 units, gave us confidence to venture into space business. which conveys the consistency in assembly and testing of these modules. In the interim, AMPL was Signatures: You have been responsible for bringing also asked by SAC to reduce the weight of the TR AMPL to its current status as industry leader in aerospace Module using Magnesium housing in place of the sector. What was your motivation and inspiration in conventionally used aluminum housings. developing such advanced RF & Microwave subsystem Signatures: Apart from RISAT-1, your team at AMPL development and testing facilities? Will you share some of had also worked on other space projects and programmes your experiences during this long journey? during last many years. Kindly also let us know about MR: During my service tenure at DRDO, I had AMPL’s contributions in the field of telecommunication realized that Private Industries can contribute and meteorology.

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Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 MR: Apart from RISAT-1, AMPL has worked for bonders, die bonders, parallel gap welders and re- GSAT-4 and GSAT-7 projects. The Ku-Band receivers flow soldering system is available in-house. Apart under fabrication will be used in the upcoming GSAT from these, a Dicing system for dicing the wafers and programs. The Ku-Band Outdoor units giving an Alumina substrates and a seam sealing system for output of 5W and 10W for GSAT programs have been hermetic sealing of metal packages are also available. fabricated and delivered successfully. This apart, All required facilities like DI water, pure Nitrogen, AMPL has developed many products for ISAC. We Vacuum and Compressed Dry Air are also made have also fabricated a C-Band Transponder for the available. Our operators and inspectors are qualified IRNSS program as a design verification model, which for all the activities like dicing, sealing, fabrication etc. is meeting the requirements of RF performance, size We have experienced Design engineers who work on and weight. For Meteorology, AMPL has worked various space-projects with the help of advanced with ISRO to develop and install Automatic Weather software like Agilent ADS. The test facilities includes Stations in various remote areas of India, helping in a number of Vector & Scalar Network Analyzers, data collection and transfer of weather data using Synthesizers, Noise Figure Analyzers, Spectrum INSAT/Kalpana Satellite. AMPL has also developed Analyzers, Power Meters, Oscilloscopes etc., that disaster communication systems called Mobile work from DC to 40 GHz. As part of diversification, Satellite Service (MSS) Terminals with technical we have initiated action for installation of in-house know-how from ISRO. These are briefcase terminals Laser Welding facility, which is expected to be that can be carried by personnel for communication functional in next six months. using a specialized MSS Transponder in INSAT. Signatures: Where does AMPL stand today technically in Signatures: ISRO has been credited with putting untiring terms of Microwave, RF and Radar technology capabilities efforts and encouraging the indigenous Indian industries in the International competitive scenario? What could be and industry participation in Indian Space programme. the future frontiers of technological challenges and Kindly share your experience with ISRO on this. advanced R&D efforts in the field of RF & Microwave MR: AMPL has learnt from SAC/ISRO development? What types of R&D efforts are put-in by methods/procedures to be followed right from AMPL? material ordering, incoming inspection, chemical and MR: In terms of Microwave, RF and Radar mechanical analysis of raw-materials and technology capabilities, today’s requirements are high consumables and various testing/inspection criteria. efficiency, miniaturization and lightweight modules We have also learned to qualify a material in case we without compromising on performance. This involves do not get the required information from the vendors. new processes like LTCC, dev. of Multi-functional Wherever there is lack of sufficient information on chip for RF applications, use of high efficiency GAN any aspect, right from assembly to testing, SAC/ISRO devices for power and improvising on packaging gives us directions to fulfill our requirements. The techniques using laser welding etc. AMPL is audit carried out by SAC on both electrical and developing devices with the state of the art mechanical fabrication always provides us with technologies upto 40 GHz for high power output insights on continuous improvement. along with good noise figures. We have started working with many reputed companies from Europe, Signatures: What types of Infrastructure and R&D set- US and Israel and are trying to expand and learn ups exist at AMPL? Are there any plans for further to keep pace with the global requirements. We diversification and augmentation? hope that using all our learning, we will soon be able MR: Our Space group has a dedicated Space to adopt the best practices available across the globe Qualified Class 10,000 clean room with a plinth area leading to more value addition for our customers. of 6000 sqft. An assembly line consisting of wire 108 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jun 2011 Signatures: What role can professional societies like ISRS as a platform where Indian industries with different play for increased industry participation in government expertise can get together and share information on bodies like ISRO, DRDO etc.? Do you have any their capabilities for achieving a common goal, for suggestions? eg., fabrication of systems for a particular payload. MR: At the outset, we are happy to know about the This will also give an understanding of industry-wide initiatives that are being taken by ISRS, Ahmedabad capabilities, thereby reducing the dependence on Chapter to interact with the Indian Industry. We look imports as far as possible. to societies like ISRS to organize events, which can act

A Brief Profile of Shri B Malla Reddy

Shri B. Malla Reddy, aged 64 years, acquired Masters in Engineering (Automation) from the Indian Institute of Science (IISc.), Bangalore. He has over 23 years of experience at the Systems Division, Indian Space Research Organisation, Bangalore and as a Scientist in the Defence Research and Development Laboratory, Hyderabad. Subsequently, he worked with OMC Computers Ltd, Hyderabad as in-charge, Software development and Head - Research & Development. Mr. B. Malla Reddy has also had the opportunity of being trained at leading companies abroad.

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Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 RS Payload Hardware- Electronics Subsystems for EO & MW Payloads

Design, Development and Delivery of Space Grade Modules and Subsystems for RS Applications from Centum Electronics Vinod S Chippalkatti, Centum Electronics Limited, Bangalore [email protected]

1. Introduction: Indian industries are trying to other sub-elements, SAR payload comprises TR leverage design strengths, manufacturing assets and Modules (TRMs), TR Control Units (TRCs), Tile best management practices to deliver the space Control Units (TCUs) and Power Conditioning and electronics hardware to achieve greater customer Processing Units (PCPUs). satisfaction [1]. Centum Electronics Limited Centum Electronics has delivered more than 360 Bangalore is the leading Indian company with focus flight model PCPUs after qualifying the specially on design, development and delivery of high designed and developed hybrid micro circuits and reliability electronic modules and subsystems for planar magnetics. PCPU is a very complex multi- defense and space applications. This paper explains output dc-dc converter that delivers around 100W of the contributions made by Centum Electronics peak power and around 10W of average power [Fig towards the realization of space grade electronic 1]. modules and subsystems for remote sensing applications.

Established in 1995, Centum Electronics initiated its line qualification to space standards in 2000. After a rigorous four phase qualification of hybrid micro circuits line, Centum started delivering microcircuits Fig. 1: PCPU developed for RISAT-1 to remote sensing and geostationary communication This unit has several ‘first-time’ sub-elements which applications since 2001-02. Subsequently, the SMT- are qualified and realized for Indian remote sensing Mixed PCB assembly and Box build lines and satellites. Three hybrid micro circuits developed and Oscillators lines are qualified by ISRO Centres along qualified for fly-back topology [Fig. 2]. with the operators and the inspectors [2]. The • HMC of size 1”X1.5” covering PWM chips, reliability screening facility is also approved for space primary MOSFETS operating on 70V bus, opto- applications. These approvals are based on ISRO- coupler in closed loop operation, TM-TC PAS-206, ISRO-PAX-300, MIL-PRF-38534-Class K, interfaces. MIL-PRF-55610 and MIL-STD-883 guidelines. This • HMC of size 1”X1” covering linear regulators for paper gives the details of the subsystems developed two outputs of the PCPU and two regulated for various remote sensing satellites of ISRO. voltages for control circuit • HMC of size 1”X1.5” covering the switching 2. Radar Imaging Satellite-1 (RISAT-1): RISAT-1 is a circuits including the MOSFETs for delivering the new class of remote sensing satellite distinct from the large peak current switching outputs. established IRS class and uses an active radar sensor system. It carries a multimode C band Synthetic Aperture Radar (SAR) as the sole payload. Amongst

110 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jun 2011

Fig. 2: Hybrids qualified for PCPU; Fig. 3: Planar Magnetics qualified for PCPU

• Process qualification for large size bare die conformance to expected patterns. Assembly of attachment and 0.7mil & 2 mil gold wire bonding. specially designed ASIC by SAC-ISRO using dam and • Planar magnetic components for EMI filter fill techniques and PROM programming are the inductor and fly-back transformer realized using important features of the TRC which is a part of the specially designed 18 layer and 16 layer PCBs Beam Steering Electronics [Fig. 4]. Around 200 Flight respectively, with copper thickness of 105 microns units have been delivered for RISAT-1. for inner layers. These planar magnetic parts are qualified at component level and also at subsystem level [Fig. 3]. • Large scale use of Magnesium alloy for weight reduction. • Heat sink assembly for high power PWM Hybrid Micro circuit to flush out the heat from the hybrid to the chassis. Fig. 4: TRC for RISAT-1 Beam Steering Electronics The TRC (Transmit Receive Module Controller) is used to control RF modules (called TR Modules), TCU-EPC [Fig. 5] is a single output dc-dc converter which transmit and receive RF signals. The digital capable of supplying 3W (5V/0.6A) power to the portion of the TRC produced at Centum receives a digital loads of Tile Control Unit. This houses main multitude of digital signals consisting of timing and redundant power supplies in one housing and is windows, a clock and serial commands (on RS422) designed to suit the mechanical dimensions of TCU. and an analog input. The unit generates several A specially designed hybrid micro circuit with size digital bit level and word level outputs. Using the 1”X1.5” covering the PWM chip, primary MOSFETS, automated Ground Checkout Unit (GCU), the input- Opto-coupler and TM-TC interface was qualified for output relations are checked for integrity and use onboard the EPC for TCU. Centum has delivered such 32 flight units for RISAT-1.

Fig. 5: EPC for powering TCU of RISAT-1

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Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 3. INSAT-3D (Satellite for Meteorological application): INSAT-3D is an advanced meteorological satellite without additional communication payload. It features a 19-channel sounder, a 6-channel imager and a DRT & SAR payload. Centum has developed six different types of hybrid micro circuits and qualified them for use onboard INSAT-3D meteorological payload Fig. 7: Power Supply Unit for Met-Payload application of INSAT-3D electronics. HDC-1, HDC-2 [Data command interface hybrids], HCS [Control Section], HGSS [Gain Selection hybrid], HIRPA [IR preamplifier hybrid] and SWIRPA [Short Wave Infra Red Pre Amplifier hybrid, [Fig. 6] are the modules used in met-payload electronics and contain circuits in analog, digital and mixed mode domains [3].

Fig. 8: Power supply stack for Electro-Optics Payload

5. Conclusion: The maturity of the space industry has resulted in increase in the number of organizations that can provide subsystems and systems for many missions than before. These industries are able to deliver the reliable and cost effective hardware. The projects undertaken by Centum are turn-key in Fig. 6: Short Wave Infra Red Pre Amplifier (SWIRPA) nature and cover concept to prototype development Hybrid and subsequently qualification model hardware to Centum has also designed; developed, qualified and flight hardware delivery. Centum procures the space delivered five output 40W Power Supply Unit [Fig. 7] grade electronic components with necessary element for Met payload application of INSAT-3D in a record evaluation and screening data. time of six months. Four different types of Hybrids Excellent infrastructure, supported with best were developed and the dc-dc design underwent manufacturing practices has enabled Centum to detailed structural, thermal, de-rating and reliability design, develop and deliver world class electronics analysis followed by actual environmental test hardware used in space application for the remote complying with qualification and acceptance levels sensing area. Apart from the subsystems mentioned [4]. Five flight units and one qualification model have in the previous sections, Centum has delivered been delivered by Centum. hundreds of hybrid micro circuits [multiplexers, relay 4. Resourcesat-2: ResourceSat-2 is an advanced drivers, dc-dc converters] and crystal oscillators remote sensing satellite and designed for the study [VCXOs, TCXOs and Clock oscillators] for and management of natural resources. Centum has housekeeping subsystems of remote sensing satellites. manufactured and tested the Power Supply stack to 6. Acknowledgements: Centum Electronics is ISRO design and has delivered nine stacks for thankful to various centers of Indian Space Research different applications. One such stack [Fig. 8] is used Organization (ISRO) for providing an opportunity to in powering Electro-optics payload of Resourcesat-2. develop space electronics hardware for remote sensing applications. Thanks are due to the 112

Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jun 2011 subsystem design teams and quality assurance teams [2] Vinod S Chippalkatti, Vedprakash G, Sandhya of ISAC, SAC, LEOS, IISU and VSSC for their Thyagarajan and Gopal Joshi, “Design and constant support and guidance throughout the development of space grade electronic modules for execution of the contracts and in ensuring that the inertial systems” ISRO Industry-meet at IISU flight-worthy hardware is delivered by Centum. Trivandrum Realization of space products is not possible without [3] KG Domadia, JV Bhale Rao, JH Bhatt, Vinod S the support of the ‘Operators and Inspectors Chippalkatti, Gayathri Kumari MB. “Development of certification committees’ of SAC, VSSC and ISAC for a 4 channel 200Meg-ohm trans-impedance amplifier conducting the theory and practical tests for Centum Hybrid Micro Circuit for space application”, operators and inspectors and certifying the Presented in IMAPS-2006 held in December 2006 in technicians. Thanks are also due to the management Hyderabad. team of Centum for their support and [4] Bhoopendrakumar Singh, Santosh Joteppa, encouragement. The contributions from the Design Satyanarayana Prasad, Vinod S Chippalkatti, and Engineering team and entire operations team at R.N.Garvalia, K.G.Domadia, R.M.Parmar, R.K.Dave, Centum are also highly appreciated. DRM Samudraiah “Design and Performance References Verification of Space Grade Multi-output Medium [1] Vinod S Chippalkatti and G Vedprakash, Power, Electronic Power Conditioner under Thermo- “Towards Design, Development and Manufacture of Vacuum Environment”, Poster presentation in IEEE Space electronics hardware by Indian Industries”, International Vacuum Electronics Conference IVEC- Presented in 20th National Convention of Aerospace 2011 held in Feb 21-14, 2011. Engineers NCASE-2006, at IE(I) Trivandrum in October-29, 30 2006.

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114 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jun 2011 Contribution to Space Projects by Astra Microwave Products Ltd

Astra Microwave Products Ltd (AMPL) started the Indian Space Research Organization (ISRO), and working on Space Related projects in the year 2003 they have been qualified for all the activities like and a separate working group was created for this dicing, sealing, fabrication etc. We have experienced purpose at its Research and Development facility Design engineers who work on various space-projects located at Hardware Park in Hyderabad. with the help of software like Agilent ADS.

AMPL space group provides a total solution from Test Facilities: The test facilities includes a number of Design to delivery of the screened Vector & Scalar Network Analyzers, Synthesizers, components/subsystems under one roof. Noise Fig. Analyzers, Spectrum Analyzers, Power Meters, Oscilloscopes etc., that work from DC to 40 Facilities: The group has a dedicated Space Qualified GHz. Class 10,000 clean room with a plinth area of 6000 sqft. An assembly line consisting of wire bonders, die bonders, parallel gap welders and re-flow soldering system is available in-house. Apart from these, a Dicing system and a seam sealing system are also available for dicing the wafers and Alumina substrates and for hermetic sealing of metal packages respectively. All required facilities like DI water, pure Nitrogen, Vacuum and Compressed Dry Air are Quality control: The quality processes followed are made available within the facility. adapted to Space requirements. Inward inspection is carried out by inspectors with experience to carry out inspection of mechanical hardware, electronic parts, raw materials and consumables. The facility includes high accuracy Metallurgical Microscope with 1000x magnification, Inspection Microscope, XRF for plating thickness measurement, Nikon profile projector with 0.01 Um accuracy, Dage Die shear and bond pull tester for the integrity of the Assembly, Sheet Resistivity tester, Adhesion Tester, pico Ammeter for IR measurements and Surface Roughness Tester for 4Delta measurement etc,. For screening, AMPL has set up climatic chambers, burn-in ovens, vibration testing, constant acceleration, PIND and Pressurization, Fine & Gross leak detectors

AMPL takes up orders for design, development and S-level fabrication as well as built to print fabrication Qualified Man power: The group has completed as per requirements specified by the customer. qualification of the assembly line for MIC and MMIC Procurement, Inspection, Fabrication and fabrication and that of the sub-systems in accordance testing/screening are followed as per ISRO with requirements for carrying out space projects. guidelines. Most of our operators and inspectors are qualified by

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Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 AMPL has rich experience of working in the Space L Band TR Modules working over 1.2 to 1.4 GHz with domain, having developed and manufactured 200 watt output are developed for MOTR project for components and sub-systems for SAC, ISAC, VSSC SHAR. and SHAR (brief details included), and we look forward to take up more challenging work in the future.

Products Supplied for Space Use: AMPL has developed Flight models S Band 8X8 Switch Matrix with least power requirement and in smaller size for G Sat- IV.

C Band TR Modules, High Power PIN diode switches, Power Distribution Networks, Calibration Net works, Integration Block, TR control unit and Tile control units are fabricated for RISAT by AMPL. AMPL has screened the RF Power devices for this development.

AMPL has fabricated and screened the Ku Band Beacon sources as per SAC document.

AMPL has developed Mesh Processor at VHF range for the GSAT applications.

AMPL has supplied number of MMIC based systems to SAC.

Apart from the onboard sub systems and components AMPL has developed the Ka Band outdoor units with 10 watts and 5 watts power to SAC.

Number of data Transmitters for X Band and S Band are supplied to ISAC for use in different satellites. This comprises of QPSK and BPSK with data rates ranging up to 200 MBPs.

X band 2 watt Amplifiers were developed for ISAC, AMPL also has fabricated X band Phase shifter Amplifiers for ISAC.

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117 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 The Ever Increasing Complexity of PCB Layout CMR Design Automation

In the Design world today, it is up to the designer to be the master of the board layout, just as the engineer Electronics Industry is constantly pushing the edge of is the master of the circuitry. One of the ways a board technology in three directions designer can exhibit that mastery is through quality • faster clocks for more throughput placement and routing techniques gleaned from • smaller packages for smaller sizes reading and understanding the manufacturer’s data • lesser power consumption sheets and application notes. All three are most relevant to satellites – process more PCB Design was carried out with Visula earlier. data, reduce the weight of the satellite, decrease the Visula was the masterpiece of PCB design and ran on power requirement in the satellite. 3 mips Apollo workstations with 128M Memories and These pushes of technology have had their direct 500 MB Disks. In hindsight to get most of the features impact on PCB design, in one to one correspondence: available today in such limited hardware capability • faster clocks means lesser rise times and less looks like a miracle. DOS machines were ruled out as leisure time available for signal to walk along the PCs were too weak with 640K memory. track. • High density design and thermal issues As time progressed and PC hardware power • lower noise margins increased and Windows became available, engineers shifted lower end PCB design software to PC based Faster rise times means that there are higher Cadstar. Cadstar was simpler, easier to use and frequencies on the board. A 1 ns rise time implies 1 cheaper than Visula, though at that time it did not and 2 Ghz signals. As signals move from 10 Mhz to have all the features of “workstation softwares”. 100 Mhz and 1 Ghz the design process moves from However due to these features, Cadstar was rapidly wires to transmission lines. Transmission lines need deployed throughout various departments and till specified impedances. This changes the total date forms the cornerstone of quality PCB design. paradigm of PCB design. The new paradigm requires that manufacturers be searched who can produce a In the past, when frequencies were low, rise times range of impedances in their processes. high and components large (non dense boards), designers used data sheets for gate and footprint Less time for the signal to walk the track means that information and wanted little else information. As delays need to be controlled. Delays controlled to 0.1 long as the layout and the routing met the ns is now common. Lower noise margins require that requirements it was a job well done. But today, the signal qualities be maintained very good. A little extra role of the designer is more important due to the noise can inject the proverbial “one in a million” increasing complexity of signals, the layer structures, wrong data and crash the system – totally the changing board materials and a variety of unacceptable. The noise margins should be such that manufacturing issues. Thermal considerations have the board should work for 10 years without a signal also become important due to density of the chips and wrong “1” “0” being clocked during this period. As their small package sizes. Designers must know how technology has got complex, so has PCB the signals behaviour and analyse and control it. manufacturing and testing. PCB designs must now They must understand how one seemingly meet new challenges in manufacturing and testing. A insignificant issue will affect other aspects of the testable design is a fundamental must. With higher design. 118 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 frequencies, both due to faster clocks and faster rise model generator is not only easy to use, accurate times, has come the “sin” of EMI (once the darling of and fast; the wizards create detailed 3D models for Marconi – who around the turn of the last century almost any electronic component. For design teams created super excitement in the electronics world by working on boards where space is tight this creating EMI over the Atlantic). A most unwanted functionality has become mission critical. CAD but omnipresent devil, EMI is limited or minimised softwares like Cadstar have kept momentum with due to a legal requirement for equipment on the earth, the constantly changing technology and are able to and for higher reliability in the sky. On the one hand meet requirements on PCB design. Various aspects EMI affects other electronics in the vicinity and on the of the design can be continously monitored and other hand EMI is energy taken away from the board corrrected as the design proceeds. This leads to a which has it own serious implications. correct design where all aspects are taken care of. Most of the PCB Design jobs are done using the Reliability: CAD softwares are not only meeting CADSTAR PCB Design software. One Example: design challenges they are also enhancing reliability. Onboard card: This was a challenging job in Using advanced thermal analysis softwares using selecting the right stack up by doing Pre Layout SI CFD techniques, temperatures of the components can analysis to finalize the trace widths and spacing’s be predicted accurately. Moving the components for differential pair and length matching signals. around the board, making intelligent compromises The differential pairs and Length matching signals between thermal and route requirements, operating were routed using Cadstar HS router. Post Layout temperatures of components in some cases could be SI analysis was done to check signals for reflection brought down. In the case of active components and / ringing and cross talk. Amends were done where semiconductors this could have a bearing on needed. It was also very essential to carry out the component MTBF. thermal analysis since this card goes into Mechanical: The integration of ECAD with subsystem of the satellite. With the export option MCAD has led to another benefit in PCB design. from CADSTAR for Thermal Analysis, the Components of various heights are used in any Thermal analysis for this board was done using PCB, and space being a costraint, the placement of COOLITPCB software. Coolit uses the most components can be checked upfront for any advanced techniques of thermodynamics for mechanical constraints. It is not only useful, but accurate analysis, namely computational fluid important to check all constraints (routing, signal dynamics. integrity, noise, thermal, mechanical) upfront and Conclusions: CAD softwares like Cadstar have kept arrive at a “consensus” before the design is done. momentum with the constantly changing technology CADSTAR has a module called Board Modeler and are able to meet requirements on PCB design. Lite which allows users to create detailed 3D Various aspects of the design can be continously models of components with the 3D model monitored and corrrected as the design proceeds. This generator. (The creation of detailed 3D models by leads to a correct design where all aspects are taken MCAD teams can be time consuming and the only care of and a successful design from all aspects is alternative is to source the data from the internet, realised in the minimum time. where only a handful of component suppliers provide detailed 3D models). This unique 3D

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Contact: SpurMicrowave Inc #414, Church Road New Tippasandra, HAL III Stage Bangalore 560075 (T) 0091 80 25272653/25213640 (F) 0091 80 25284223, [email protected]

121 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

Komoline’s Journey into India’s Space Sector Komoline Electronics Pvt. Ltd Komoline was established in 1990. It has in-house Terminals, MSS-C Terminals, Distress Alert design, development, test and manufacturing facility Transmitter and Automated Weather Stations. of hi-reliability Space and Defence applications. We have contributed in Remote sensing projects Komoline has accumulated experience of almost 15 starting from building custom build Test Setup and years in the fabrication of sub-assemblies for calibration unit for first TRModule. It was done Communication and Remote Sensing payloads before TR Controller came into existence. onboard ISRO’s satellites like INSAT-4A, INSAT- 4B/4C, INSAT-3D, GSAT-3, GSAT-4, GSAT-5, RISAT- 1, OCEANSAT-2, etc. We have capabilities of fabricating space grade MIC- MMIC based “Ku, C, S and UHF Band” RF subsystems like LNA, Driver Amplifiers, Receivers, LOs, Beacon Source, Beacon SSPA, HYBRIDs, Up- Convertors etc. We also fabricate Hi-reliability Analog and Digital PCB Assemblies for Payload having Through Hole, SMT and Fine Pitch TR Module test & Calibration unit for RISAT-1 Components. Automated ASIC Test Setup (AATS): Komoline has Our Hi-rel certified team is also qualified for developed Automated ASIC Tester System (AATS) Crimping joints, Multipin Co-axial R.F. connector, for OBC-1 ASIC for TR Controller for RISAT-1 radar. Harnessing of wires/cable, Local potting of All the TR Controller ASICs were tested before lid component, Radiation shielding of component, cutting and bending using this AATS. Connector fitting (D-type, OSM etc), Panel fitting, Gasket Application, Thermal tape application, Araldite application, Conformal Coating, Epoxy application and Inductor/transformer winding for Payload Fabrication. We have delivered custom made Automated Test Equipments and Simulators for Payload test and check-out. Some of these equipments are GPS Simulator, S-Level ASIC tester, DDS based 16 Channel RF Synthesizer, INSAT Telemetry- Telecommand Simulator (TCTM) and TR Module controller Check-out system. GPS Simulator: GPS Simulator was build to simulate We have also delivered Satellite Ground Application all the conditions of GPS indoor and had provison of products like L-Band SatCom Modem, L-Band Image connecting Real GPS to offer actual GPS data. Reject Down-Converter, ASIC Based PSK Demodulator, Ka Band Indoor Terminals, MSS-D

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TR Controller (TRC) for RISAT-1 Radar: Complete production (fabrication, assembly & Environmental Testing) of TR Controller (TRC) for RISAT-1 was also FPGA based Test Jig: FPGA based design and done at Komoline. development tool was built to be used as test jig for various digital subsystems for projects like RISAT-1, Oceansat-2 etc.

Degaussing Set-up for Dam & Fill: Custom made vacuum chambers and pumps were built for

degaussing of Dam & Fill done on Onboard Ground Check-Out Unit for TCU: TCU-GCU (Tile Controller (OBC) ASICs for TRC & TCU. Control Unit Ground Checkout Unit) was built for automated test setup of TCUs in production line. Complete conditions were simulated and automated reports of each TCU were generated. Apart from IBT it was used in every stage of testing including Thermovac, Vibration and EMI/EMC.

Production of RF Cables: Flexible group-delay matched RF Cables (blue colour cables visible in photograph of RISAT-1 tile) were produced in large quantities (~3000 Nos.) by Komoline for RISAT-1 Project.

Tile Control Unit (TCU) for RISAT-1 Radar: Production (fabrication, assembly & Environmental Testing) of Tile Control Unit (TCU) for RISAT-1 radar was done at Komoline.

123 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Ambimat’s Contributions to Space Activities

Ambimat Electronics was founded in 1982 by Shri We also take great satisfaction and pride to enlist our Durgesh Shah, who himself was an Ex-employee of significant contributions in the following technical Space Applications Centre, Ahmedabad. Over these projects of SAC/ISRO in the last decade : years, Ambimat has acquired in-house capabilities of design, development and testing of electronics • Spacecraft Interface Simulator (command & subsystems. Since last more than two decades, it has monitoring unit) been actively contributing towards various technical • Data Handling units for IRS ground check-out support requirements of the Dept of Space, Govt. of • Detector Head Assembly (DHA) test units India. • Signal Processing units • QPSK modulator units Ambimat has been involved in the execution of • Payload Status iIdicator units projects involving electronics subsystems for ground • Online Monitors for check-out & integration support and check-out instrumentation related to • Fabrication & testing of Payload Controller various Remote Sensing and Communication units payloads onboard ISRO’s satellites like IRS-1 & P • Design and Fabrication of cable harness tester series, RISAT-1, OCEANSAT-2, Megha Tropiques etc. • Design & Fabrication of Control unit for C- and has gained more than 20 years of experience. band up-converter The other contributions made by M/s. Ambimat • Design & Fabrication of Control unit for Ku- Electronics for various Onbaord Subsystems for band up converter Payloads as well as ground check-out equipments are • Design & Fabrication of tracking chain as follows: selection units • Fabrication of spacecraft interface simulator • Multi-Layered PCB Layout Designs For for INSAT payload (Imager P/L) / (Sounder Different Projects Through Contracts; P/L) with active online monitors • Design , Development , Fabrication And • Design & Fabrication of signal select units and Testing Of Custom Built Electronic Equipment test signal select units for Antrix corporation For Ground Use Including Necessary ltd. Packaging As Per Requirements On Turnkey FPGA test system capable of program Basis ; • development and testing of FPGAs. • Contributing To Technical Services By Development and Supply of interface unit for Providing Suitably Trained Engineering And • Automatic Weather Station (AWS) data Technical Support Personnel To Carry Out reception And Support Following Activities At Sac • Fabrication of Data Acquisition Interface with • Analog And Digital Electronics Design, computer Development & Testing

• Fabrication For Ground / Onboard Applications The photographs below give a glimpse of the products • RF and Microwave Electronics Related and subsystems successfully fabricated, tested and Testing delivered by Ambimat in last few years.

• RF and DC Harness Fabrication For On OUR VISION and COMMITMENTS: We, at Ambimat Board Applications Electronics, are also committed to create for our team • Mechanical Design & Drafting 125 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 an environment conducive to progressive and with SAC/ISRO and strive to excel in timely innovative thinking by facilitating learning through delivering of excellent quality products and services continuous exposure to evolving technologies. We to justify the faith our esteemed customers like also take pride in all our achievements while working SAC/ISRO have bestowed on us.

AWS DATA INTERFACE

PAYLOAD CONTROLLER

DATA HANDLING UNIT CONTROL UNIT FOR UP-CONVERTER

Call for Articles

Readers are requested to contribute short articles for publication in the forthcoming issues in their own

words, preferably as per the editorial calendar given on page-4, either as a brief survey of state of the art or as articles on specific work carried out by them, or as novel concepts related to the specific theme(s). The deadline for inclusion in the next issue on “Atmospheric & Oceanic Remote Sensing” is Sept 20, 2011. - Editorial Team

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127 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

128 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Integrating Relationships… Suresh Mirchandani – Director, Bryka.

It gives me immense pleasure to write this article on as per the Government guideline was through an our association with Space Scientist & Engineers at official public tender. Through proven technical organisations like SAC/ISRO which spans over a capability and commercially competent solution, yet decade now. again Aeroflex was selected for the fabrication of the Onboard Controller (OBC) ASIC. Bryka/Aeroflex has been associated with various projects for multiple Hi-Rel Products. However, We understand that multiple such OBC ASICs have developing ASIC has been nothing short of a been used Central Data Management and antenna Herculean task. Aeroflex is SMD, QML Q and QML V beam control Unit of RISAT-1, which is a Remote supplier of Microelectronics. They have a DSCC Sensing Earth Observation Satellite designed to (Defense Supply Centre Columbus) certified provide services in the areas of Natural Resource Radiation Hardness Assurance Program. Aeroflex Management of Agriculture, Forestry, Water produces components that are qualified to Military Resources, Climatic Studies & Scientific Performance Specifications such as MIL-PRF-38534 Observations over Tropical Countries. The major and MIL-PRF-38535. features of OBC ASIC are mentioned below:

With the advancement in technology and increasing complexities of Space Hardware, the emphasis was very much on VLSI. Keeping pace with the trends in technology, Aeroflex at that time was already developing and supplying Hi-Rel ASICs for various customers across the globe. India being successfully developing and launching Satellites caught the attention of Aeroflex. Being aware of the technical expertise of ISRO, Aeroflex was very much keen in Functional Features of OBC ASIC: participating with the development of ASICs. To • 8 bit embedded microcontroller (DW8051) • 3 Timers and 5 Interrupts minimize the size, weight and the effective cost for the • 4 asynchronous serial I/O ports (UART) launch of bulky Space Hardware, ISRO too decided to • 3 synchronous serial Transmitter/ Receiver opt for RadHard ASICs. (SSR/SST) • 10 parallel I/O ports (80 bits) Multiple meetings, endless discussions, late evening • 16 programmable timing signal generation teleconferences earmarked the beginning of the first • 256 bytes of auxiliary data RadHard ASICs for ISRO during 2003-04. With the transmitter/receiver passage of time and more exposure to the design • Two 8 bit Delta Sigma ADC modules tools, simulators and process technologies; the • Watchdog Timer for Software hang detection • Power saving by Selectively clock enable requirements for more complex ASICs were already generation on the cards. The development of 6 different ASICs • On chip monitor program for debug test for ISRO by 2006-07, demonstrated Aeroflex’s • 1K Bytes of on chip SRAM superior product and service. By this time there • All Flip flops are radiation Hard were other new entrants to the RadHard ASIC • JTAG boundary scan chain market. The selection of fabricator for the OBC ASIC Technological Feature of ASIC: 129 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 • CMOS pure digital implementation approval. The transition from a mere design • 0.6μ CMOS RadHard Gate Array Technology requirement to a fully functional ASIC was definitely • 5 Volts I/O with 5 Volts Core the outcome of the uncompromising support and help • Ceramic Flat Pack (CQFP) with 256 pins , 224 extended by ever-so talented Senior Scientists and QA User I/Os Officers and Program Managers. • Testability features like SCAN and ATPG with logic Fault Coverage of > 95% With the emergence of powerful digital signal Radiation: TID > 100Krad, SEL LET > 125 • processors implemented in CMOS VLSI technology MeV-cm2/mg, and high-resolution Analog to digital (A/D) • SEU no upset,per storage element ≤ 1 x 10-10 errors/bit – day converters that can be used as an interface between • Screening : Optimized QML-V the digital and the analog world, there is much • ESD sensitivity level of the device: as per test emphasis on Mixed-Signal ASICs. Aeroflex has method 3015 (2KV). already begun fabrication and supplies of Mixed • Max Clock Frequency: 16 MHz Signal ASICs for various prestigious mission • 300K NAND2 equivalent gates (~900K worldwide and is keen on participating for Transistor Pairs) opportunities with ISRO.

Bryka/Aeroflex strongly desires to maintain excellent There were Preliminary Design Reviews (PDRs), business relationship with ISRO and is looking Critical Design Reviews (CDRs) and Final Design forward for future requirements to work together. Reviews (FDRs) prior to the sign-off and fabrication

Engineering Capabilities of Spur Microwave Inc Spur Microwave Inc

Spur Microwave Inc is a technical marketing RF & microwave components & sub systems company providing services and solutions in the Offices at important locations in India and abroad area of space, defense, avionics and other harsh within proximity reach of the customers. environment applications where reliability is critical. Vision: To become market leader of products, services, and solutions in supporting the Indian Our engineering capability has been established and space, defense and avionics industry Spur India proven over a decade to provide adequate expertise committed to realize this vision with four dedicated in the area of high reliability components, RF & endeavor: growth, operational excellence, financial microwave components and subsystems. stability and continuous education.

Strengths: High reliability components & sub systems

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131 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Data Patterns’ Participation in Space Programme Data Patterns (India) Private Limited, Chennai Phone: 044-4741 4000, Fax: 044-4741 4000 [email protected]

Data Patterns is glad to be part of many of the Space programs. These enabled us to enhance our analytical and technological strengths through interactions and to contribute successfully with our state of the art design and manufacturing technologies.

Data Patterns specializes in the development, manufacturing and support of Defence and Aerospace systems. Data Patterns has core competences in Avionics, Displays, Radar,

Navigation & Control, Fire control, RF & Microwave, Automatic Test Equipment and associated Embedded High Precision Data Acquisition System (HPDAS) and Application software packages. The Company provides solutions for land, sea and air platform Data Patterns has developed Design verification applications for Defence segment and for satellite and model of a modular high precision data acquisition launch Vehicles in space segment. Data Patterns is an system for Megha-Tropiques project. Detailed design ISO 9001-2008 and AS 9100 company. It is also an analysis, detailed circuit design, worst case error approved Design and Test agency for Airborne analysis by applying progression of errors, Electronics Products by CEMILAC. Data Patterns has refinement of performance specifications at ambient, a total talented manpower of 400 + out of which 200+ hot and cold environments, mechanical design, PCB engineers are in product development and design, component procurement, assembly, test in engineering. 100000 Sq Ft of modern Development ambient, hot and cold temperatures were carried out and Production facilities has been set up in Chennai. successfully. The sections below describe some of the projects Data Patterns could contribute significantly jointly executed for SAC by Data Patterns, Chennai. with the help of SAC on the theoretical analysis as well as realization of the unit, with constraints that two units are to be made identical in function and performance, but with Core FPGAs from two different vendors viz. Xilinx and Actel. The highlights are the common design to work with FPGA from two different vendors, 11.8 bits ENOB performance using a 12-bit ADC, temperature measurement with 0.5 degree accuracy, pulsed current source to avoid self heating of thermistors during measurement, and component selection with devices having same footprints for MIL and RAD Hard devices as for industrial devices used in DVM. Another important

aspect was the signal to be acquired, was actually a

132 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Guassian Noise, and apart from testing the modules for standard static, dynamic and temperature tests, The Ground Checkout Unit of the Transmit Receive the performance and ability to measure Guassian Control module (TRC-GCU) for RISAT-1 radar, was noise with 11.8 ENOB performances had to be built using off-the-shelf cPCI I/O boards and cPCI demonstrated, which required synthesis of Guassian chassis and system integration was carried out noise within the signal dynamic range, using Matlab along with application software that was delivered generation of data and generation using function as a turn-key solution. The checkout is capable generators of the data set. testing functionally 12 TRCs in a single setup daisy The system has nine high precision analog input chained. The programming data generation, channels that acquire and process signals from communication via serial I/O in custom formats of passive microwave radiometer sensors. In addition it SAC, verification of parallel and serial acquires temperature data from multiple thermistors. programming data outputs and simulation of It is realized in five modules Multi Channel Digitizer Thermistor measured voltages for calibration module, Temperature Data Acquisition module, performance against temperature were verified Digital Integration and Control Module, Power using this checkout and 400 UUTs have been tested conditioning module and a mother board, each successfully. module with its own chassis and I/O. The MCDM is built using Xilinx FPGA (MCDM I) and Actel FPGA(MCDM II). Data Patterns is proud to have participated and thankful to SAC for the opportunity to demonstrate the ability to carry out high reliable, high performance, rugged design and the ability to theoretically predict and achieve the predicted performance and also the acceptance being completed smoothly without any hitch for the DVM using the Conclusion: Apart from the above projects, we checkout, which was also developed by Data have supplied a range of test systems to other ISRO Patterns. laboratories for Launch vehicles, Onboard satellite package etc. Our manufacturing facility is also Ground Checkout Units for HPDAS and Transmit certified for Space package production. Receive Control Module We believe that we can offer solutions using cutting The checkouts offered were turnkey solutions edge technologies in various domains like Signal where the constituent boards and instruments, Processing, RF & Microwave, Digital IF and FPGA system integration and the software development solution, Communication, Control & Navigation, were with Data Patterns. The development of a key Displays, Product development and Software. I/O general purpose interface board, DP-3510 with an uncommitted Xilinx XCV300 FPGA, was Data Patterns expresses its sincere thanks for the employed for the checkout of the system along opportunities, active participation, co-operation with other instruments and standard off the shelf and technical guidance from SAC. cPCI boards and cPCI chassis from Data Patterns.

133 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Xilinx FPGAs: the X-link of Space Applications Rajesh Subramanian, Neeraj Varma [email protected] [email protected]

There has been a paradigm shift in space applications. • Easier prototyping Today’s spaceborne payloads are required to deliver • Re-programmability of the FPGA is a major asset complex applications with ever increasing demand for innovative reconfigurable or adaptative for: system designs (not all space FPGAs) a) Speed • Transforming commercial components into b) Bandwidth space qualified ones: use of commercial IPs c) Reliability • IP on an FPGA: rich portfolio, solves d) lower power obsolescence problems for long term requirements Aerospace industry community is constantly trying to derive a semiconductor, which can match the above Xilinx offers flexibility to the engineering requirements. However, when the specifications are community by its tool set which allows, varities of worked out to create that perfect semiconductor; they Xilinx users to utilize it in their own domain of finally end-up making an Applications Specific expertise, as mentioned below : Standard Product (ASSP), which again fulfills • Matlab or System users: can use Xilinx System requirements of only a few applications. Generator to do their designs Programmable Logic Devices (PLDs) help the • Embedded users: can use Xilinx Platform Studio engineering community to build their Application to do their embedded design Specific or Centric Standard System which can be re- • Common user: can use Xilinx ISE to implement used as a System or can be a subsystem for future their custom logics upgrade. Execution/Implementation of complex • Test engineers: can use Xilinx Chipscope on-chip applications puts a lot of stress on the engineers. debug tool or Xilinx ISIM for simulation Engineers are always looking at a device- which has • Advanced users: can mix and match all the following features; above tools and use platform studio. a) Reduce time to market

b) Cost effective Xilinx has been associated with SAC for many years c) Re-using of the custom IP now. Xilinx is proud to be part of few of the most d) Easy of use advanced and complex payloads developed by e) Reduce risk SAC/ISRO like RISAT-1 radar, Oceansat-II

Scatterometer, GSAT-4 regenerative Payload and Xilinx plays the X-link (cross-connect) to connect the Airborne DMSAR. Therein Xilinx Virtex-XQVR600 need and execution of such demanding projects. FPGA’s were used to interface with high speed data Xilinx FPGAs, which once used to be part of the VLSI converters like ADC & DAC subsystems. Xilinx domain are now merged into the Embedded systems FPGA’s were used to implement Fast Fourier domain due to their flexibility to offer System-on-Chip Transform (FFT) for simultaneous estimation of Signal designs. and noise-only energies. FPGA were also used for Xilinx FPGAs also offer many System-level application based on signal processing tasks like advantages for driving applications mainly; digital integration, filtering and offset/gain • Reducing system dimensions corrections, custom timing & control logic. Xilinx’s • Innovative & complex architectures associating rich heritage of the usage of various IPs in other on a same chip (µP cores, memory blocks and specific logic functions) 135 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 market domains like communications brings in more resistors required for impendence matching by confidence as it is tested all along for many years. implementing inside FPGA e) Creating internal high speed clocks using Xilinx has always lived on applications, Application DCM/PLL engineering team works very closely with SAC f) XTMR tool helps implement selective TMR Engineers/Scientists by providing technical support design at a click of button for component selection, resolving of application g) Xilinx ICAP and Partial reconfiguration helping implementation issues and constantly helping them to satellite ground station to upload a new scale the imaginative power of the scientist for actual application to a distant space payload without implementation within a short time. interruption of current application

Xilinx Virtex, Virtex-4 & Virtex-5 FPGA’s are currently being used or planned for complex payload which enable; a) Interfacing high speed data convertors ADC & DAC of sampling rate more than 1 Gsps using

Xilinx FPGA resources like IOSERDES b) Moving from parallel I/Os to serial I/Os for Xilinx have recently introduced Virtex-5 RadHard better signal integrity using Xilinx LVDS helping FPGAs (Single upset Immune Re-configurable FPGA) used to communicate speeds upto 1 Gsps devices, which will hopefully change the architecture c) Very High speed SERDES for data transfer more of all future communication and Remote Sensing than 1 Gbps payloads. We at Xilinx are committed to work with d) Digitally Controlled Impendence (DCI) helps the SAC/ISRO for future payloads which will make India system engineer to cut down on external as greatest super-power in 21st century.

Call for Articles

136 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

With Best Compliments from Compusense Automation 404/405 ISCON Plaza, Opp. Home Tower, Satellite, Ahmadabad Contact: Mr. C R Vaidya [email protected]

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138 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 FPGA & ASIC Design Services from CoreEL Technologies

CoreEL Technologies (formerly CG-CoreEl in terms of FPGA performance and cost in a timely Programmable Solutions) have been associated with manner is our key differentiator. SAC/ISRO on various projects. CoreEL offers end to CoreEL technologies have done major Front-end end FPGA & ASIC Design Services for its customers design of On Board Controller-1 (OBC-1) ASIC for across various Industry Verticals. Being one of the RISAT-1 radar project. It included functional early starters in India; we have continuously verification of RTL designs provided by SAC, enhanced our skills and have kept pace with the changing programmable logic technology. The design synthesis, STA, formal verification, Scan and JTAG methodology evolved over the years has made us insertion and final generation of gate level netlist robust and capable of handling designs of any ready for back-end design. The Figure below shows complexity. Our ability to meet customer expectations OBC-1 ASIC Front-End design flow.

The major functional features of OBC-1 ASIC, which • 10 parallel I/O ports (80 bits) (out of which 6 were exhaustively verified by Corel and SAC design ports are “event controllable”) teams are as follows: • 16 programmable timing signal generation • 8 bit embedded microcontroller (DW8051) • 256 bytes of auxiliary data transmitter/receiver • 3 Timers and 5 Interrupts • Two 8 bit Delta Sigma ADC modules for • 4 asynchronous serial I/O ports (UART) digitization of slow varying analog signals • 3 synchronous serial Transmitter/ Receiver • Watchdog Timer for Software hang detection (SSR/SST) • Power saving by Selectively clock enable generation 139 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 • On chip monitor program for debug test Table-1 • 1K Bytes of on chip SRAM Activity Tool Name • All Flip flops are radiation Hard • JTAG boundary scan chain Simulation Modelsim5.8e Lint Check Vncheck 2005.03 The table-1 shows different activities carried out by us for OBC-1 ASIC design in coordination with Code Coverage Vncheck 2005.03 SAC/ISRO’s ASIC design team. Synthesis Synopsis DC & DesignWare Lib. The Top-level functional verification was carried out very exhaustively with total 431 test cases to test all Scan Insertion DFT Advisor possible modes and corner cases of OBC ASIC. LRC Rule check Aeroflex toolkit CoreEL technologies have done all this activites in close-association with SAC design team engineers. Formal Verification FormalPro There were regular interactions and mutual visits STA PrimeTime between SAC engineers and CG-CoreEL, Bangalore design team during various design phases of OBC SDF Generation Aeroflex toolkit ASIC. Regular monthly progress reviews were Boundary Scan BSD Architect provided by CG-CoreEL. Preliminary Design Insertion Reviews (PDRs) and Critical Design Reviews (CDRs) were conducted prior to the ASIC netlist sign-off for the back-end designer and foundry services. CoreEL technologies are proud to be associated with such a complex and challenging ASIC design and look forward to take up similar design projects as well as board and subsystem level design projects for SAC’s future payloads. We also wish success to ISRO’s future space programmes.

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142 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Digital Signal Processing Unit for Space Use Trident Infosol Private Limited Trident Infosol Private Limited was set-up with a IEEE 1101.10/11 standards, enclosures give advanced mission to bring to the Indian embedded market the EMC shielding protection and are available with a best-in-class solutions in COTS hardware and wide range of options. Based on a modular packaging application development tools. Since 2000, it has been approach the system can be configured by selecting successfully delivering cost-effective solutions to the the backplane, PSU device modules and the number product developer. We support a wide range of of slots. Engineered for superior cooling chassis is applications in aerospace and defense, consumer and available with bottom airflow. The chassis will accept Industrial electronics, Telecommunications, 6U cards mounted vertically. cPCI system is Automation, Transportation, Automative and Medical configured with Front I/O & rear I/O card cage. The Electronics. With offices in Bangalore, New Delhi, basic chassis features powder coated covers for a Hyderabad, Chennai, Kolkata, Thiruvananthhapuram scratch resistant, attractive finish with standard and New Mumbai, it has more than 20 years of handles on most models. experience of in-house design, development, test and 6U CompactPCI Single Board Computer (SBC) : It is manufacturing for various types of digital subsystems @2.16 GHz Intel Core Duo processor T7400 board based on COTS solutions along with chassis and occupying single cPCI slot and with dual PMC sites enclosures, including ruggedized units for aerospace and upto 4GBytes of DDR2-400 ECC SDRAM and applications. The ability to provide a complete end-to- standard interfaces like 10/100/1000Mbps Ethernet, end solution over a product development cycle with option for PICMG 2.16, Packet Switch backplane, USB extensive application support is our distinct hallmark. 2.0 interfaces, Serial ATA150 HDD interfaces, On- For some of SAC/ISRO’s prestigious remote sensing board EIDE interfaces (up to UDMA100) and programmes like Oceansat-II, IRS Series, RISAT and Graphics, keyboard and mouse interfaces. It has board Megha Tropiques, Trident Infosol Pvt. Ltd., has been support packages for Windows XP/ XPE/ associated in one way or the other. Over last ten or 2000/Server 2003, Linux, VxWorks and QNX more years, we had been providing COTS cPCI and PCI boards and cPCI chassis for the development of 6U cPCI Octal TigerSHARC DSP Boards: The T2-6U- Ground Check-Out units for these programmes. One cPCI (T26U) is a 6U CompactPCI board featuring such challenging task was the delivery of Digital eight ADSP-TS201 TigerSHARC DSPs from Analog Signal processing unit for SAC’s radar projects. It Devices. To take full advantage of the high included design, development and delivery of the performance TigerSHARC, the T26U implements following modules/units for this very complex BittWare’s ATLANTiS, which combines robust system: TigerSHARC processing with the versatile Xilinx Virtex-II Pro FPGA to offer ultra high performance 1) Chassis for 16 Slot 6U cPCI Cards with and unprecedented I/O bandwidth. T26U is an Ideal 1500watt Power Supply 2) 6U CompactPCI Single Board Computer(SBC) : choice for high-performance applications, such as Dual-Core CPU, Single Slot , Dual PMC sites radar and sonar and it combines the ADSP-TS201 3) 6U cPCI Octal TigerSHARC DSP Board TigerSHARCs and FPGAs with High-bandwidth, low- latency off-board I/O, reconfigurable for nearly any Chassis for 16-Slot 6U cPCI Cards with 1500watt application, High-speed interprocessor Power Supply : The cPCI enclosure provided is communications to facilitate scalability, SharcFIN elegant and versatile platform for packaging desktop bridge for integrating DSPs with PCI bus and or rack mount Compact PCI applications. Designed to peripherals and Comprehensive software for ease-of- 143 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 use. It has Two clusters of four ADSP-TS201 DSPs @ and 2 Tbytes respectively, with a sustained up to 500 MHz and delivers 28.8 GFLOPS (3.6 throughput of 6-8 GFLOPS. The overall configuration GFLOPS of floating-point power per DSP). The T26U necessitates about 80 to 100 TigerSHARC DSP’s @ is part of BittWare’s T2 board family, which features 250/500 MHz. It is being housed in a single 16-slot the ADSP-TS201 TigerSHARC DSP on a variety of cPCI chassis, consisting of about 6-8 boards and platforms. The boards all feature a common, scalable TigerSHARC based PMC modules. architecture - ATLANTiS - and are available in PCI-X The figure below shows the above-mentioned COTS plug-in, PMC, 3U cPCI, 3U VPX, 6U VME, and 6U and Other modules supplied by M/s. Trident Infosol CompactPCI form factors. Pvt. Ltd. For this Digital Signal Processing system. We understand that using the above systems and Trident Infosol Pvt. Limited is very happy to learn COTS DSP and other boards supplied by Trident about these DSP system related developments and Infosol, SAC/ISRO’s DSP design team is configuring takes pride in being associated with such an important radar signal processing system for its various and prestigious project of SAC/ISRO. We wish the spaceborne and Airborne Radar projects. The total project team all the success in their efforts and assure computing power, memory bandwidth and them of our full cooperation, technical and application RAID/JBOD data storage requirements for these development related support. systems are of the order of 2-120 TFLOP, 3-8Gbytes

16-Slot cPCI Enclosure SBC cPCI module 6U Tigersharc DSP Board

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144 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

146 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 RS Payload Hardware- Product Development Tools

Product Development System with PTC Windchill Production-proven content and process management processes. The result: you can finally align product software: Whether your organization is a global development with strategic corporate goals, and conglomerate, a regional supplier, or a small service improve your business results. bureau, you face many obstacles trying to manage product content and development processes. The fact is, your organization’s success relies on having efficient business processes and effective development of complex information assets, including product designs, service documentation, and regulatory submissions. Windchill, PTC's Product Lifecycle Management (PLM) software for managing product content and processes, offers a powerful, proven solution. Fast, secure, and Web-based, this business collaboration software enables companies to streamline product development processes and deliver superior physical goods and information products. Features & Benefits

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process. With all levels of content–from final assembly Windchill PDMLink not only captures, conFig. s and structures to individual components – conFig. d, manages product information during every step of the managed and stored in a one central repository, product lifecycle, but it also effectively supports your everyone within the enterprise can now immediately company’s initiatives to optimize key business access the same product information.

148 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

Reduce process errors and engineering rework: location, activities and events can now be monitored, Windchill PDMLink includes a comprehensive allowing you to identify potential bottlenecks or Change Management process that can both ‘fast-track’ duplicate tasks. your simple, low cost changes and ‘full-track’ extensive modifications, all while automatically About PTC: PTC (Nasdaq: PMTC) provides discrete documenting revision and iteration histories. manufacturers with software and services to meet the Windchill PDMLink gives global manufacturers the globalization, time-to-market and operational ability to consolidate scattered product information efficiency objectives of product development. For and bring order to chaotic development processes. more information on PTC, please visit, With its powerful content, configuration and change http://www.ptc.com. management capabilities, Windchill PDMLink helps About Adroitec: Adroitec Engineering Solutions (P) you drive product success. Ltd is an ISO 9001 Certified Global Engineering Support global product development: Windchill Solutions provider. With a team of over 300+ highly PDMLink was designed to support distributed qualified and experienced professionals, Adroitec product development with a Web-based architecture delivers, implements solutions and services which are that can coordinate replicated databases around the closely aligned with the design-through- world. Now anyone, anywhere within the enterprise manufacturing strategies of its global manufacturing or extended supply chain can communicate and customers, crashing cycle times and reducing costs. collaborate on product development. Regardless of http://www.adroitecengg.com.

149 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

Jaivel Congratulates ISRS – Ahmedabad Chapter for its contribution towards society and continuous effort for betterment of people using Remote Sensing Technology.

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Jaivel is a leading supplier to the Aerospace Industry of End to End Manufacturing Engineering Solutions. Jaivel collaborates with its customers and assists them to achieve a superior service performance, through effective and efficient implementation of technology and innovation. The company currently has three global centers of excellence in India and United Kingdom. Jaivel enables swift and efficient “New Product Introduction” (NPI) within a clients manufacturing facility and also supports the entire manufacturing lifecycle of the products when necessary, delivering continuous process improvements therefore assisting the customer to meet the OEM’s year on year cost reductions.

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Jaivel Synergies Pvt. Ltd. Rajkot(India) P: +91–281–2364004 E: [email protected] W: www.jaivel.com

151 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

152 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

With Best Compliments from Innovative CAD/CAM Services Adhana Estate Samrat Indl.Area-12, Gokuldham Main Road, Rajkot.

Contact: KELVIN MAKADIA [email protected]

153 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Remote Sensing Satellite Launch & Test Facilities Taking Part in Indian Space Dream Shankar Ghosh, Shell-N-Tube, Pune - 411040

Thirty years ago, on July 18, 1980, with the successful flight of Satellite Launch Vehicle-3, India became one of the few countries capable of launching satellites. The venture was not intended as a way of breaking into an exclusive club. Rather, it was a necessary and important step towards realizing the dream of Vikram Sarabhai, the visionary who established the Indian space programme and imbued it with a great constructive mission. "We must be second to none in the application of advanced technologies to the problem of man and society which we find in our country," he declared.

Satellites would provide cost-effective communications and broadcasting in a vast country Fig. 1: PSLV C-16 Lift Off like India with poorly developed infrastructure; earth the indigenous Indian Remote Sensing (IRS) imagery would permit efficient management of its satellite program to support the national economy natural resources; and space- based cameras could in the areas of agriculture, water resources, forestry keep constant watch on the weather. Technology must and ecology, geology, water sheds, marine fisheries not be imported as a black box, and India must both and coastal management. build its own satellites and put them in orbit on its rockets, insisted Dr. Sarabhai. It took ten years to Towards this end, India established the National develop SLV-3, a launcher with modest capabilities Natural Resources Management System (NNRMS) modeled on the Scout rocket of the United States. This for which the Department of Space (DOS) is the was the breakthrough event. After another nodal agency, providing operational remote experimental rocket, the Augmented Satellite Launch sensing data services. Data from the IRS satellites is Vehicle (ASLV), the Indian Space Research received and disseminated by several countries all Organization built the Polar Satellite Launch Vehicle over the world. With the advent of high-resolution (PSLV). This now launches operational earth imaging satellites new applications in the areas of urban satellites (Fig. 1) and propelled the Chandrayaan-I sprawl, infrastructure planning and other large spacecraft on the first leg of its journey to the Moon. scale applications for mapping have been initiated. The Geosynchronous Satellite Launch Vehicle (GSLV) The IRS system is the largest constellation of is successfully launching communication satellites and remote sensing satellites for civilian use in a more powerful version of it, the GSLV Mark III, is operation today in the world. With the launch of under development. RESOURCESAT-2, the constellation now has eleven satellites in operation – IRS-1D, Following the successful demonstration flights of OCEANSAT-1 & 2, Technology Experiment Bhaskara-1 and Bhaskara-2 satellites launched in Satellite (TES), RESOURCESAT-1 & 2, 1979 and 1981 respectively, India began to develop CARTOSAT-1, 2, 2A & 2B and IMS-1. All these are placed in polar sun-synchronous orbit and 154 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 provide data in a variety of spatial, spectral and the fleet of IRS satellites and widening their temporal resolutions. applications. The journey was not always smooth – obstacles had to be overcome – solutions found to technical

Fig. 2: Liquid Hydrogen Level Sensor Bath Data from Indian Remote Sensing satellites are used for various applications of resources survey and management under the National Natural Resources Management System (NNRMS). Following is the list Fig. 4: Liquid Nitrogen to Helium Gas Heat Exchanger of those applications: situations and problems for the first time, Indian • Pre harvest crop area and production estimation of industries had to be involved as it became obvious major crops. to the planners of Indian space program that there • Drought monitoring and assessment based on is no substitute to development of our own vegetation condition. technology since importing technology particularly • Flood risk zone mapping and flood damage in areas such as cryogenics, optics, propulsion will assessment. not be shared by any member of the existing space • Hydro-geomorphologic maps for locating club. No incident symbolizes this overt act of underground water resources for drilling well. technology denial to Indian space industry like • Irrigation command area status monitoring when Soviet Union under US pressure refused to • Snow-melt run-off estimates for planning water transfer the technology of cryogenic engines along use in downstream projects with the engines ordered. So the technology had to • Land use and land cover mapping be developed in the country jointly by Indian space • Urban planning research organization and Indian industries in the • Forest survey private sector. • Wetland mapping It was in fact a blessing in disguise to a plethora of • Environmental impact analysis Indian Industries like Shell-N-Tube (SNT) who • Mineral Prospecting joined in to fulfill the technical challenges and meet • Coastal studies the national objective of developing a self sufficient • Integrated Mission for Sustainable development sustainable space program built on home built (initiated in 1992) for generating locale-specific technical solutions in all key technical areas. prescriptions for integrated land and water resources development in 174 districts. Our involvement started with supply of first

Indian manufactured multilayer insulated vacuum RISAT, RESOURCESAT-3, CARTOSAT-3 & jacketed piping and stainless steel ambient heated OCEANSAT-3 are the remote sensing satellites liquid nitrogen vaporizer to SHAR launch complex planned by ISRO to be launched next strengthening way back in 90s (Fig. 2, 3).

155 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 When the US instigated technology denial regime One of the major challenges for this gigantic launch came into being for cryogenic technology, SNT got a vehicle is the development of C-25 engine capable challenging opportunity for getting involved in of generating 20 ton thrust using liquid oxygen and cryogenic upper stage project or CUSP as ISRO took liquid hydrogen as propellant. To test this massive steps to make indigenous cryogenic engine with 7 ton cryogenic engine, an elaborate test facility is being thrust to be used in the Geo-Synchronous Launch set up in Mahendragiri and Shell-N-Tube has Vehicles GSLV MK-II. ISRO needed a composite heat participated in the venture by successful exchanger to cool liquid oxygen and helium gas with development of the following cryogenic systems. liquid nitrogen as expendable refrigerant. This involved development of multi layer insulation - 150 mm multi-layer insulated vacuum jacketed technology, low conductivity support system for piping for feeding liquid oxygen and liquid cryogenic vessels, high efficiency pool type cryogenic hydrogen to C-25 turbo pumps in the turbo- heat exchange equipment and of course development pump test facility. The integrated piping of high vacuum and mass spectrometer leak testing system is already in operation. capability with 100% indigenous equipment and - 48 g/sec dual pressure circuit liquid nitrogen to technology. helium gas cooler (pool type heat exchanger) with multi-layer vacuum insulation. We developed this exchanger successfully in the - 48 g/sec dual pressure circuit liquid hydrogen project schedule time frame. This was the first such to helium gas cooler (pool type heat exchanger). heat exchanger in India. This LOX-GHe cooler is still being used at LPSC steering engine test facility for - Multi-layer insulated vacuum jacketed liquid nearly 15 years without any problem (Fig. 4). Also we hydrogen bath for level sensor calibration/ designed and successfully supplied multi-layer command gas bottle validation etc. insulated vacuum jacketed cryogenic pipeline systems suitable for working pressure up to 81 bar But this, we believe, is just the beginning. As ISRO another first in the country. sets its sights higher, we are sure industry This was followed by getting involved with SAC participation in all its activities including remote Ahmadabad for designing and supplying an efficient sensing will only go deeper and wider. cryogenic pipe line system to feed their thermo- vacuum test chambers which was done successfully and in record time.

As the communication need of the nation grew so did the demand for heavier communication satellites and consequently larger satellite launch vehicles came into reality like GSLV MK 3 capable of putting a 4-6 ton satellite into geosynchronous orbit.

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157 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Upgradation of Instrumentation Control & Data Acquisition System for 5.5 m Thermal vacuum Chamber Prima Automation (India) Pvt. Ltd.

1. Existing system before up-gradation task: This of old Software with latest one, development of system was installed in year 2002 having Hot SCADA in WinCC Ver7. Redundant, Fault tolerant mode consisting of Main Now system is having Two Servers & Three Clients (vacuum) PLC systems of 400 series (CPU 417-4H) (one client located near plant), System Operation & and Thermal PLC system 300 series (CPU 315-2DP) Visualization (from Servers as well as Clients) with with 1100 and 300 distributed Analog & Digital enhanced feature like Menu Driven Screen Inputs & Outputs respectively through Profibus Navigation, Sub-system wise Process Screen network. Other instrument having serial data were development with different layers and enhanced interfaced through Industrial PC with PLC for data graphics through standard WinCC library tools ( acquisition from different field instruments. Three resulted into 33% of total number of screens WinCC Ver5 based Servers (no client configuration) compared to earlier one ), Improved Event / Alarm for Operation & Visualization, data storage / Data Storage of Analog & Digital data (for 1200 retrieval for Report Generation was developed with data), Graphical Plotting 400 analog data, VB and Crystal Reporter. Considering experience in development of system wise Data tables to view operational requirements, to take care of future historical data and extract into CSV format, Report needs, as well as computer hardware getting generation into Excel formats, through Data Monitor obsolete, required Upgradation taken up. tool (into 200 predefined templates). Security 2. Contribution in System Upgradation: In the year modeling for each operator /user is traced by using of 2010, Prima Automation (India) Pvt. Ltd. was Security modeling for Log-in/Log-out from entrusted for this task of Upgradation of terminals. The look of the entire control room has Instrumentation, Control & Data Acquisition System now changed as new stations are high end machines for 5.5m Thermal Vacuum Chamber at Space with much bigger size, speed and aesthetic appeal. Application Centre, Ahmedabad. Task included Supply, Installation & Commissioning, of PCs and SCADA, Networking of PLCs & PCs, up-gradation

View of 5.5m TVC control console Menu driven navigation screen on one terminal

158 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Payloads for Resourcesat-2 Himanshu K Dave Space Applications Centre, Ahmedabad-380015 [email protected]

1. Introduction: This article describes the designed in such a way that any single point failure configuration of Resourcesat-2 payloads, will not jeopardize the multispectral imaging improvements with respect to Resourcesat-1, capability. LISS 4 can be operated both in Mx mode performance observed during payload development and mono mode based on the user requirement. and also includes their in-orbit performance. Using increased onboard storage, it is now feasible to Resourcesat-2 (RS-2) is a follow-on spacecraft for the provide full 70 km swath of all three bands of LISS-4 Resourcesat-1 (RS-1) and is configured to provide as compared to 23.5 km in Resourcesat-1. continuity of data along with enhanced performance. LISS-4 is realized using 12K Linear CCD having 8 RS-2 has an objective to support data services on an ports with a pixel size of 7μ X 7μ. The drive operational basis for integrated land and water electronics is placed very close to the CCD. The resources management. It will also be used for payload electronics consists of timing logic, video studies like improved crop discrimination, crop processing, calibration and interface electronics. The yield, crop stress, pest disease surveillance, disaster timing logic is realized using FPGAs to cater to the management etc. Resourcesat-2 was launched on CCD clock requirements as well as synchronization April 20, 2011 from Shriharikota. The spacecraft was clocks for digitization and calibration. The video put into a sun synchronous polar orbit at an altitude processor consists of amplifiers, ADC, and FPGA for of 817 km. After initial spacecraft operations, digital signal processing. It receives analog video payloads were operated from April 28, 2011 onwards. signal from the CCD and digitizes to 12 bits and Payloads have been providing excellent imageries, generates 10 bit video data which after compression since then. (DPCM) is available as 7 bits for transmission. In addition, the payload electronics also generates the Three tier imaging spacecraft Resourcesat-2 carries controls for onboard calibration by varying exposure electro-optical payloads namely LISS-4, LISS-3* and control of CCD. Camera electronics has been AWiFS. All the three payloads are multi-spectral miniaturized and there by mass, power and volume push-broom scanners with linear array CCDs as have been significantly reduced. During Resourcesat- detectors. The high resolution imaging with IGFOV 1 there were nine packages which are now only four of 5.8 meters is carried out in 3 spectral bands by packages. The weight is reduced to 9 kg from 31 kg. LISS-4 camera and medium resolution images with IGFOV of 23.5 meters is available in 4 spectral bands Radiometric improvements have also been carried through LISS-3* camera. AWiFS camera provides out. LISS-4 camera uses 10 bit digitization, however, high temporal resolution data in 4 spectral bands to match the data transmission, 7 bits were utilized. with an IGFOV of about 56 meters. In view of this, in Resourcesat-1, bit sliding (selection of 7 bits out of 10) was chosen based on the radiance 2. Brief description of the payloads: settings requirement. This has been overcome in LISS-4 Payload: LISS 4 is a high resolution Resoursesat-2 using the DPCM compression multispectral camera with three spectral bands viz technique where 10 bit data is compressed to 7 bits B2, B3 & B4. LISS-4 Camera is facilitated with off- for transmission which is reconstructed to 10 bits on nadir viewing capability in across-track direction (± ground. Because of this, simultaneous data can be 26 deg). This helps in reducing the revisit period to 5 acquired which is made independent of scene days. It has 16 in-flight calibration levels. It is radiance.

161 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

Fig. 1 Configuration Schematic of RS-2 Payloads Fig. 2 A Schematic of RS-2 Payload Ground Coverage

Performance achieved during integrated payload have been done in RS-2 in terms of radiometric tests is given below: resolution i.e, 10 bits instead of 7 bits. Moreover DPCM technique is used like in LISS 4 to transmit 10 Parameter Performance bit information using 7 bits; to ensure backward SNR @Saturation compatibility with RS-1 for the data interface with B2 353 Base band data handling system. The VNIR Camera B3 367 Electronics packages are mounted on the electro- B4 274 optic module structure while SWIR electronics LISS-3* Payload: LISS 3* payload has four spectral package is mounted on the spacecraft deck. Camera bands i.e, B2, B3, B4 & B5 with independent optical electronics has been miniaturized and there by mass, assemblies and a linear array detector for each chain power and volume have been significantly reduced. providing identical IGFOV of 23.5 meter. All bands During Resourcesat-1 there were eight packages provide 100% albedo coverage with 1023 levels of which are now only four packages. quantization. LISS 3* uses refractive optics for all four spectral bands. Each optical assembly consists of 8 refractive lens elements with the interference filter and the thermal filter. LISS-3* camera has an in-flight calibration using LEDs. It is designed in such a way that any single point failure will not jeopardize multispectral imaging capability.

The detector used for each VNIR band is a 6000 element CCD with a pixel size of 10 micron * 7 micron on a pixel pitch of 10 microns and has two Fig. 3 LISS-3* Band-2 Radiance Discriminability ports. The detector for SWIR band is a 6000 element Radiometric improvements have been carried out. CCD with a pixel size of 13 micron X 13 micron on a LISS 3* camera uses 10 bit digitization in pixel pitch of 13 microns having two ports. Resourcesat-2 and mapped to 7 bits using DPCM algorithm. Subsequently, reconstructed to 10 bits on ground. Also the sensors capability has been The camera electronics consists of bias generation enhanced to 100% albedo. NESR has improved to electronics, clock driver circuits, video processing, 0.05 mW/cm2/Sr/μ with respect to 0.25 timing & control logic, calibration logic, calibration mW/cm2/Sr/μ in RS-1 as shown in Fig. 3. The drivers and interface electronics. Enhancements discriminability of the target is enhanced to photon 162

Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 noise limited. power and volume have been significantly reduced. During Resourcesat- 1 there were 12 packages which In-flight calibration device has been changed which are now only seven packages. AWiFS payload uses has reduced the mass on detector head assembly and 12 bit digitization (as against 10 bits during avoided complexities which were present in Resourcesat-1) and provides 10 bits for data Resourcesat-1. transmission so as to maintain data rate. This has Performance achieved during integrated payload been achieved using multi linear gain (MLG). This tests is given below: scheme provides enhanced radiometric resolution at Parameter Performance lower scene radiances. SNR @Saturation Performance achieved during integrated payload B2 767 B3 803 tests is given below: B4 716 B5 864 Parameter Performance SNR @Saturation AWiFS-A AWiFS-B AWiFS Payloads: The Advanced Wide Field Sensor B2 752 763 (AWiFS) payload is designed to cater to the high B3 756 762 B4 763 763 temporal resolution requirement of RS-2 mission B5 1049 1062 with revisit period of 5 days. It has IGFOV of 56 meter at nadir from an altitude of 817 km. AWiFS Miniaturisation of electronics: As explained earlier has four spectral bands, three in the visible and near in each camera, the miniaturisation of electronics IR (B2, B3 and B4) and one in the short wave infrared has been carried out. The camera electronics (SWIR, i.e., B5) similar to AWiFS of RS-1. hardware is realized using passive SMDs, FPGAs The AWiFS camera is configured as a set of two and extensive use of multiplayer PCBs resulting in identical payloads i.e., AWiFS 'A' and AWiFS 'B' significant improvement in terms of size, weight squinted with respect to nadir to provide a swath and power. A total mass reduction of ~70 kg, and larger than 700 km. It has an in-flight calibration power of ~30% is achieved. The improvements were available using LEDs. 16 intensity levels for VNIR implemented initially in the bread-board model and bands and 6 intensity levels for SWIR are available to adequacy established. Subsequently, these have cover the dynamic range. Full albedo coverage is undergone qualification tests and validation of the available with single gain. In addition, provision performances in extreme environmental condition. exists to tune the radiance value onboard using Following this, flight model hardware development exposure width selection. Failure of any chain is not have been carried out and tested. catastrophic. It reduces the swath by a factor of 0.5. In-orbit Launch Performance: After the launch, in- Each camera has four independent lens assemblies, orbit performance evaluation of all payloads have detectors and associated electronics catering to the been carried out and it has been observed that the four bands. The imaging concept is based on push cameras are performing exceedingly well. Payload broom scanning like in the other two payloads ie operating temperature and gradients for all cameras LISS 4 and LISS 3* and uses a linear array CCD are found to be as expected. Voltage telemetry placed in the focal plane of the optics. An overlap of parameters are found to be consistent. First day 150 ± 20 pixels is kept for swath continuity. images have been analyzed and found to be The camera and detector electronics for each matching with ground performance. SNR for LISS- detector chain is separate and independent. Camera 3* is found to be ~600 and more. The LISS-4 camera electronics has been miniaturized and there by mass, image analysis indicates that more than 90%

163 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 dynamic range has been covered simultaneously. Acknowledgements: The author is grateful to Dr. R AWiFS shows high radiometric performance as R Navalgund, Director, SAC for providing the expected. Sample images received from each opportunity and permission to write this paper. The payload are included below. author thanks Shri A S Kiran Kumar, AD, SAC for his encouragement in bringing out this paper. The author appreciates the keen efforts taken by Shri D.R.M. Samudraiah, DD-SEDA for his guidance in making this paper. The author also thanks the GHs, Heads and Managers of various divisions of SEDA, MESA, SRA and Facilities in SAC. Finally, the author is grateful to the dedicated team of Scientist and Engineers who have contributed for developing

the state of the art flight worthy Resourcesat-2 Fig. 4 Comparison of SWIR Electronics packages of RS-1 Payloads. The author also thanks Data Products & RS-2 team for providing the ground support. Specifications of LISS-4, LISS-3 & AWiFS camera are given in Table-1.

Table-1: Specifications of LISS-4, LISS-3 & AWiFS cameras

PARAMETER VALUE LISS-4 LISS-3 AWiFS Ground Sampling Distance (m) 5.8 23.5(at nadir) 56 (at nadir), 70 (off- nadir) Swath (km) 70 (Mono and Mx mode) 141 740 Spectral Bandwidths (μ) B2 B3 B4 B2 B3 B4 B5 B2 B3 B4 B5 0.52- 0.62-0.68 0.77-0.86 0.52- 0.62- 0.77- 1.55- 0.52- 0.62- 0.77- 1.55- 0.59 0.59 0.68 0.86 1.7 0.59 0.68 0.86 1.7 Quantization Bits 10 (7 bits after DPCM) 10 (7 bit Tx after DPCM) 12 (10 bit Tx with MLG) Signal to Noise Ratio @ >128 >128 > 512 (for all bands) camera saturation Saturation Radiance 53 47 31.5 53 47 31.5 7.5 53 47 31.5 7.5 (mW/cm2/sr/μm) Square Wave Response (%) >20 >20 >20 >30 >30 >20 >20 >30 >30 >20 >20

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LISS-3*

165 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

Forthcoming Remote Sensing Related Conferences Oct 17-19, 2011 Jakarta, Asia Geospatial Forum, http://www.asiangeospatialforum.org/ Indonesia

Nov 8, 2011 Bhopal, India ISPRS WG VIII/6, VIII/8 & ISRS Joint international Workshop ON Earth Observation for Terrestrial Ecosystems, Web site: www.commission8.isprs.org/wg6/ and www.commission8.isprs.org/wg8/ Nov 9-11, 2011 Bhopal, India ISRS-2011, National Symposium on Empowering Rural India through Space Technology & Annual Convention of ISRS, www.isrs2011bhopal.org Aug 25- Sep 01 Melbourne, XXII International Society for Photogrammetry & Remote Sensing 2012 Australia Congress, Contact: [email protected]

166 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Microwave Remote Sensing Signatures of Precipitation and its Retrieval over Land and Oceans R.M. Gairola Space Applications Centre, Ahmedabad-380015

1. Introduction: Satellite microwave remote sensing based assessment of rainfall, thus become inevitable. has been successfully used to monitor the temporal This leads us to a plethora of problems starting from and spatial variations of sea surface and calibration of the sensors measuring the radiant atmospheric properties on global scale since the intensity at the top of the atmosphere (TOA), launch of the Soviet Cosmos-243 instrument in 1969. development of retrieval algorithms that relate the Microwaves, due to their long wavelengths, achieve TOA radiances to the vertical structure of the better penetration and interact strongly with the rainfall and other hydrometeors and the use of cloud. These measurements provide a direct cloud resolving models so that realistic conditions of physical basis for parameter estimation. In the the atmosphere are used in the estimation of the beginning, algorithm for oceanic parameter retrieval geophysical parameters. Microwave measurements was developed for observations from Nimbus-5 from space can provide estimates of water vapor, Electrically Scanning Microwave Radiometer ocean surface winds, sea surface temperature, sea (ESMR) by Wilheit et al.(1977) and Wilheit & Chang ice – concentration & several parameters such as, (1980). India launched the first remote sensing rainfall, soil moisture etc., as a function of the TOA satellite Bhaskara-I in 1981 followed by Bhaskara-II radiances. Out of this number of parameters, for in 1983 with a Satellite Microwave Radiometer brevity we exemplify retrieval of rainfall from active (SAMIR). With the advent of this satellite, a lot of and passive microwave measurements here. expertise has been gained for the retrieval of ocean- atmospheric parameters from microwave sensors. Passive Microwave Characteristics of Rainfall - Despite the obvious limitations associated with the Land and Oceans: The issue of rainfall estimation low sampling frequency of orbiting platforms over the land and oceans is of high importance due carrying microwave sensors and well known “beam to the large differences in monitoring capabilities. filling problem” which is assumed to be the largest While the ocean surface has a low microwave error source in instantaneous retrieval of emissivity ~0.5 that produces good contrast of parameters, the successful use of passive atmospheric phenomena against a low brightness microwave-based parameter estimates in temperature background, the land surface applications from various fields, encourages the emissivities are usually close to unity, making continuation of efforts towards the development of atmospheric features more difficult to identify more advanced retrieval algorithms. The recent against higher brightness temperature background. availability of detailed precipitation observations In addition, the land surface emissivities are not jointly obtained by the first space-borne microwave only variable in space and time but also very precipitation radar (PR) and a multi-frequency complex to model since they are modulated by passive microwave radiometer, TMI, on NASA - vegetation, topography, flooding and snow, among JAXA’s TRMM satellite offers such an excellent other factors. opportunity for studying the three dimensional structures of rainfall (Simpson et al. ). Limitations also originate in the multiple Among many atmospheric and oceanic parameters, hydrometeor profiles that can be associated with a quantitative assessment of precipitation continues to set of multi-frequency microwave measurements be one of the most difficult problems of (i.e. lack of a unique solution). The indeterminacy meteorology, oceanography and hydrology. Satellite over land retrievals is also due to the warm

167 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 background brightness temperatures that limit the Utilizing the frequency and polarization low frequency observations (i.e. 10, 19 and 22 GHz). discrimination of passive microwave measurements In addition, the atmospheric events produce from space, it has been successfully demonstrated polarization and the polarization difference can be that satisfactory rainfall retrievals both over land identified under various weather conditions from and oceanic areas are feasible with the sensors like satellite microwave measurements. The polarization ESMR onboard Nimbus-5, SMMR of Seasat, SSM/I processes from the surface and atmosphere can be on DMSP and TRMM, having frequencies around simulated using various radiative transfer models. 6.925, 10.65, 18.7, 22.235 and 85 GHz. The flow Surface polarization can be taken into account by charts for both empirical and physically based using different surface emissivities for vertical and rainfall algorithms are provided below in Fig. 3a horizontal polarizations. and 3b.

Microwave characteristics of ocean and land are shown in Fig 1. at standard frequencies of TRMM radiometer as an example.

Fig. 1 Microwave characteristics of ocean and land are shown for 10, 19, 21, 37 and 85 GHz frequencies of TRMM radiometer

168 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

Fig. 2 TRMM-TMI Spatial variation of BT(85.5 GHz) for convective and stratiform region and (b) Corresponding vertical cross section of Radar Reflectivity (dBZ)

Fig 3.a Conceptual Diagram for Retrieval- algorithm Empirically Based

169 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011

Fig. 3b Conceptual Diagram for Retrieval- algorithm RT Based

Examples of Rainfall Retrievals: available from MSMR measurements were wind IRS-P4-MSMR: Oceansat-1, also known as Indian speed, cloud liquid water, water vapour and surface Remote Sensing Satellite IRS-P4 was launched by temperatures over the global oceans (Gohil et al., India on 26th May 1999. This satellite carried a 2001). MSMR frequencies and channels are nearly Multichannel Scanning Microwave Radiometer similar to those of radiometers flown on Seasat, (MSMR) and an Ocean Colour Monitor (OCM) Nimbus satellites. Attempts have been made for onboard. MSMR provided measurements of rainfall estimation from MSMR, (Fig 4) taking brightness temperatures at 6.6, 10, 18 and 21 GHz advantage of the signal dominantly from microwave frequencies in both horizontal and vertical absorption/emission of clouds and rain systems polarizations. The operational geophysical parameters (Varma et al. 2002).

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Fig. 4 Rainfall retrieved from IRS-P4-MSMR and TRMM-PR brightness temperatures from radiometer and ground SSM-I Rainfall Retrievals: The scattering based radar, rain gauges and space based radar like characteristics of rain can be developed using PR are used as in a following functional form combination of the 19, 22 and 85 GHz channel, both over Indian land and oceanic regions separately, by RR (mm/h) = f(SI, PCT) establishing a relationship between the scattering index and the rain rate using the combination of Number of algorithms have been attempted by passive microwave (SSM/I-TBs) and active TRMM PR various investigators so far. For brevity the results of rainfall (Mishra et al. 2009, Gairola et al. 2010). Since the mentioned algorithm are presented below using the 19 and 22-GHz channels are relatively unaffected SSM/I data on global passes for a day based present by scattering, these observations from SSM/I are used and NOAA based algorithms for comparison and for estimation of 85 GHz brightness temperatures assessment (Fig 5). Currently, several techniques are during non-scattering conditions. being used for rainfall retrieval like non-linear regression, Bayesian approach and neural network Rainfall can be estimated as a function of both approach. Scattering Index (SI) and Polarization Corrected Temperature (PCT) over land and oceans separately. For this purpose a large data base of collocated

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Fig. 5 Examples of rain rate using present (a) and NOAA (b) algorithms for SSM/I

Rainfall from TRMM – Radiometer (TMI) and TRMM Microwave Imaging radiometer (TMI) with a Precipitation Radar (PR): The TRMM includes three complementary VIS and IR sensor for rain estimation principal types of instruments. The first and most called VIRS. The complete description of sensor innovative of the three is the first quantitative package of TRMM and some of the performance precipitation radar (PR) in space, providing height characteristics of the TMI channels are provided by profile of precipitation content from which the profile Kummerow et al. 1998. An example of Rainfall of latent heat release can be estimated. The second retrieved from TRMM radiometer (a) and Radar (b) by type of instrument is a combination of cross track NASA, and by algorithm from SAC (c) is shown in scanning multichannel dual polarization passive Fig. 6.

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Fig. 7 TRMM Rainfall for July 2002 and 2003 over Indian land and oceans Finally it is important to assess the algorithms by it is well established that the most appropriate applying in certain process studies and applications. instrument is a multi channel imaging microwave By generating monthly maps of rainfall the radiometer. The Megha-Tropiques (MT) is an Indo- performance of monsoon could be assessed. As an French mission planned for the study of tropical water example, Fig 7 below shows the July rainfall for two cycle and convective systems. The mission scheduled consecutive years of 2002 (bad monsoon year) and for the year 2011. The unique low inclination orbit of 2003 (a good monsoon year). 20 deg of the satellite ensures adequate coverage of the tropical regions with high repitivity (Raju et al. ) In Information gap and Future Scope (Megha- MT the especial emphasis will be the ocean- Tropiques and GPM): Even though much work has atmosphere interactions, the energy and water been done in geophysical retrievals, physically based exchanges in the tropical atmosphere, with the special microwave radiative transfer packages coupled with a stress on clouds and precipitation. fast and robust retrieval algorithm are still in In MT, the proposed MADRAS (Microwave Analysis developing phase. Furthermore, large gaps exist in and Detection of Rain and Atmospheric Structures) databases in respect of atmospheric states and system is a five-channel, self-calibrating, microwave hydrometeor profiles over the Indian region (both radiometer system. This radiometer is designed to over the land and the ocean). With monsoons and estimate atmospheric water parameters in the tropical tropical cyclones being India specific, some of the belt. The choice of the channels has been driven by future missions would be able to address these their potential contribution to the measurement of the problems. parameters defined above, from the experience of processing other radiometer data. Table 1 below To estimate atmospheric water parameters (like, shows the brief description of MADRAS sensor. rainfall, total water vapor, cloud liquid water, ice etc.),

Table 1: Channel of MADRAS and their related mission objectives

Channe Frequency Polarization NEΔT Spatial l No. Resolution Mission M1 18.7 GHz H+V 0.5 K 40km Rain above oceans M2 23.8 GHz V 0.5 K 40km Integrated water vapour M3 36.5 GHz H + V 0.5 K 40km Liquid water in clouds, rain above sea

173 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 M4 89 GHz H + V 1.0 K 10km Convective rain areas over land and sea M5 157 GHz H + V 1.0 K 6km Ice at cloud tops

The inadequacy of the present data sets are reflected Precipitation Measurement (GPM). For the GPM, a by the partially documented studies of the life cycle of constellation of polar satellites with TMI type of tropical mesoscale convective systems, constraints in sensors is suggested, and one mother satellite carrying the definition of specific mission etc. The answer to a Precipitation Radar. Megha-Tropiques is also an these problems lies in the repetition of the integral part of GPM to encompass the above measurements in the tropics. TRMM follow-on mentioned objectives. missions are now oriented exclusively on Global

Fig. 8 The GPM Constellation

Acknowledgements: Various levels of TRMM and [4] Mishra, A., R. M. Gairola, A. K. Varma and V. K. SSM/I, data products from NASA-GSFC, used in the Agarwal, 2010: Journal of Geophysical Research, 115, present text are thankfully acknowledged. D08106, doi:10.1029/2009JD012157. [5] Raju, G. and N. Karouche, 2009: International References: Conference on Megha-Tropiques Science and [1] R. M. Gairola, et al., SAC/EPSA/AOSG/M-T/SR- Applications, March 23-25, Bangalore, India. 48/2010 [6] Simpson, J., C. Kummerow, W. -K. Tao and R. F. [2] Iguchi, T., et al., 2000: Journal of Applied Adler, 1996: Meteorology and Atmospheric Physics, Meteorology, 39, 2038-2052. 60, 19-36, doi: 10.1007/BF01029783. [3] Kununerow, C., et al. 1998, J. Atmos. Ocean. Technol., IS. 809-817.

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New ISRS-AC Members (April 2010 to March 2011)

Name Designation Email Dr.Y.T.Jasrai Professor, Botany Dept.GU [email protected] Jaimin B Rami Scientist, GPMD/OPMG/MESA [email protected] Anugag Verma Scientist, GPMD/OPMG/MESA [email protected] Dilipkumar R Patel Scientist, GM-EnTF/ESSA [email protected] Yogesh Verma Scientist, SPEC/SIPA [email protected] Neeraj Mathur Scientist, LPMD/OPMG/MESA [email protected] Y.P.Rana Scientist, TTID/PPG/ SAC/ISRO [email protected]/gov.in Jolly Agrawal Tech. Asstt., OSG/SEDA/SAC [email protected] Parul Singh Scientist, SFSD/EOSG/SEDA [email protected] Axshay Anand Student, CEPT Uni Ahmedabad [email protected] Anish R Saxena Scientist, GPID/EOSG/SEDA [email protected] Somya S Sarkar Scientist, RFOD/EOSG/SEDA [email protected] Amitvikram Kurulkar Scientist, RLOD/EOSG/SEDA [email protected] Manish Saxena Scientist, SSD/EOSG/SEDA [email protected] Ashish Srivastava Scientist, SFED/SEG/SEDA [email protected] Vishnukumar D patel Scientist, SFED/EOSG/SEDA [email protected] Rohan P Thakker Student, Botany Dept, Guj Uni [email protected] Moumita Dutta Scientist , RFOD/EOSG/SEDA [email protected] Varunika Jain JRF, ABHG/EPSA/SAC/ISRO [email protected] Dr. Arun Bhardwaj Scientist, SSD/EOSG/SEDA [email protected] Barkha Gupta Scientist, RLOD/EOSG/SEDA [email protected] B.S.Raman Scientist, MCED/MSDG/MRSA [email protected] Munn Vinayak Shukla Scientist, ASD/AOSG/EPSA [email protected] Manik Mahapatra JRF, SAC/ISRO [email protected] Nilesh M Desai Scientist, MSDG/MRSA [email protected] Dharmendrakumar Pandey Scientist, AID/ATDG/EPSA [email protected] U.S.H.Rao Scientist, SFED/SEG/SEDA [email protected] Sukamal Kumar Pal Scientist, RFOD/EOSG/SEDA [email protected] B. Narasiha Sharma Scientist, LPID/EOSG/SEDA [email protected] Dr. Tanumi Kumar Scientist, EHD/ABHG/EPSA [email protected] Mitesh M Nadiadwal Scientist, PLID/EOSG/SEDA [email protected] Arunima Dasgupta JRF, SAC/ISRO [email protected]

Forthcoming Chapter Activities Aug 6, 2011 National Remote Sensing Day Celebrations at Shri Seva Samaj Sharda

Mandir, Varnama, District Vadodara

Sep 2011 L N Calla Memorial Lecture Sep – Oct, 2011 Seminar for Chapter Members

Nov-Dec 2011 Educational Excursion

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Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 DOS Adopts Remote Sensing Data Policy: RSDP- 2011

Recognising that Remote Sensing data provides much 2. For acquisition/ distribution of remote sensing essential and critical information - which is an input data within India, license/permission from the for developmental activities at different levels, and is Government of India, through the nodal agency, also of benefit to society; shall be necessary.

Noting that a large number of users - both within and a) Government reserves the right to select and permit outside government, use Remote Sensing data from agencies to acquire/ distribute satellite remote Indian and foreign remote sensing satellites for sensing data in India. DOS shall be competent to various developmental applications; decide on the procedure for granting license/ permission for dissemination of such data, and for Taking into consideration the recent availability of the levy of necessary fees. very high-resolution images, from foreign and b) To cater to the developmental needs of the commercial remote sensing satellites, and noting the country, the National Remote Sensing Centre need for proper and better management of the data (NRSC) of the Indian Space Research Organisation acquisition/ distribution from these satellites in India; (ISRO)/ DOS is vested with the authority to acquire and disseminate all satellite remote Recognising that national interest is paramount, and sensing data in India, both from Indian and that security consideration of the country needs to be foreign satellites. given utmost importance; The Government of India adopts the Remote Sensing Data Policy (RSDP) -2011 i. NRSC shall enter into appropriate arrangements containing modalities for managing and/ or with DOS for acquiring/ distributing data from permitting the acquisition/dissemination of remote IRS within the visibility circle of NRSC’s sensing data in support of developmental activities. receiving station(s). ii. NRSC and/ or Antrix Corporation Ltd., shall be Department of Space (DOS) of the Government of competent to enter into agreements with foreign India shall be the nodal agency for all actions under satellite operator(s) for acquisition/distribution this policy, unless otherwise stated. of foreign satellite data in India. However, NRSC will distribute the data as per terms agreed to 1. For operating a remote sensing satellite from with Antrix Corporation Ltd. India, license and/ or permission of the Government, through the nodal agency, shall be iii. NRSC shall maintain a systematic National necessary. Remote Sensing Data Archive, and a log of all a) As a national commitment and as a “public good”, acquisitions/ sales of data for all satellites. Government assures a continuous and improved observing/ imaging capability from its own 3. For acquisition and distribution of IRS data for use Indian Remote Sensing Satellites (IRS) in countries other than India, the Government of programme. India, through the nodal agency, shall grant b) The Government, through the nodal agency, shall license to such bodies/ agencies of those countries be the sole and exclusive owner of all data as are interested in the acquisition/ distribution of collected/ received from IRS. All users will be IRS data, as per specific procedures. provided with only a license to use the said data, and add value to the satellite data. a) The Antrix Corporation Ltd. (of DOS) is vested c) Government reserves the right to impose control with the authority for receiving the applications over imaging tasks and distribution of data from for grant of license for acquisition/ distribution of IRS or any other Indian remote sensing satellite, IRS data outside of India; to consider and decide when it is of the opinion that national security on the granting of license within the policy and/ or international obligations and/ or foreign considerations of the Government, and to enter policies of the Government so require. into licensing agreements with the prospective users on behalf of the Government. Antrix

179 Signatures, Newsletter of the ISRS–AC, Vol. 23, No.1 & 2, Jan-Jul 2011 Corporation Ltd. shall also be competent to levy i. Government users namely, Ministries/ such fees for granting licenses as may be Departments/ Public Sector/ Autonomous considered appropriate by it. It shall also be Bodies/ Government R&D institutions/ responsible, where necessary, for rendering any Government Educational/ Academic further help/ guidance needed by the license. Institutions, can obtain the data without any b) The Government reserves right to impose further clearance. restrictions over imaging tasks and distribution of ii. Private sector agencies, recommended at least IRS data in any country when it is of the opinion by one Government agency, for supporting that national security and/ or international development activities, can obtain the data obligations and/ or foreign policies of the without any further clearance. Government so require. iii. Other private, foreign and other users, including web based service providers, can 4. The Government prescribes the following obtain the data after further clearance from an guidelines to be adopted for dissemination of interagency High Resolution Image Clearance satellite remote sensing data in India: Committee (HRC), already in place. a) All data of resolutions up to 1 m shall be iv. Specific requests for data of sensitive areas, by distributed on a nondiscriminatory basis and on any user, can be serviced only after obtaining “as requested basis”. clearance from the HRC. b) With a view to protect national security interests, v. Specific sale/ non-disclosure agreements to be all data of better than 1 m resolution shall be concluded between NRSC and other users for screened and cleared by the appropriate agency data of better than 1 m resolution. prior to distribution; and the following procedure shall be followed: 5. This Policy (RSDP-2011) comes into effect immediately, and may be reviewed from time-to- time-by Government.

Call for Articles

deadline for inclusion in the next issue on “Atmospheric & Oceanic Remote Sensing” is Sept 20, 2011. - Editorial Team

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Signing off

Dear Reader, A dedicated small team of enthusiastic members including the editorial team from ISRS- Ahmedabad Chapter have facilitated the compilation of a number of articles and advertisements from industry professionals for this special issue of signatures. Their efforts are sincerely acknowledged. Specifically the efforts of Shri. Nilesh M Desai, Dr. (Ms) Abha Chhabra, Shri KP Bharucha, Shri. DNVSSN Murty, Shri. R P Prajapati, Shri. K G Domadia, Shri. Nitin Thacker, Shri C.P. Dewan, Shri. D R Patel, Shri. S Sarkar, Ms. Sunanda Trivedi, Shri. RK Arora, Smt. Arundhati Misra, Shri. Y P Rana, Shri Amit Shukla, Shri Yogesh Verma & Shri. Subodh P Kachhella are to be particularly mentioned for the considerable number of industry contributions to this issue.

The size of the Newsletter has been gradually increasing and has now crossed 180 pages. However, thanks to the advertising agencies, we are able to bring out this issue as a print volume in colour for the benefit of our readers. We thank the past & present Presidents of ISRS, namely Dr. Shailesh Nayak & Dr. R. R. Navalgund apart from Dr. V. S. Hegde, Chairman & Managing Director, Antrix Cooperation, Dr. T. K. Alex, Director, ISRO Satellite Centre & Dr. V. K. Dadhwal, Director, National Remote Sensing Centre for sending their messages & our past chairman of ISRS-AC Shri. A S Kiran Kumar for writing a preface for this issue. We thank Dr. R. R. Navalgund, President, ISRS & the two industry leaders for sparing their time for interviews by Signatures team, all contributing authors, the ISRS-AC office bearers for their support and particularly thank our Secretary Smt. Parul Patel and Chairman Shri. DRM Samudraiah for their active support & suggestions.

Each member of the Editorial Team has contributed in some way or other in bringing out this Issue. Shri. Yogesh Verma has particularly contributed in formatting this voluminous issue. We thank Shri. R P Dubey, SAC for conveying his views on our past issue. Please send in your contributions for our future issues and any feedbacks on the current issue to the email: [email protected]. Themes for the forthcoming issues are listed in page-4 of this issue. For the Editorial Team, R. Nandakumar

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Signatures

Newsletter of the Indian Society of Remote Sensing –Ahmedabad Chapter

Volume: 23, No.1 & 2, January - July 2011

ISRS-Ahmedabad Chapter

Room No-4372,

Space Applications Centre (SAC),

Indian Space Research Organisation (ISRO),

Ahmedabad-380015, Gujarat,

Phone: +91 79 2691 4372

Editorial Team

R Nandakumar, SAC

Subodh Kachhela, SAC

Shweta Sharma, SAC

Amit Shukla, SAC

Yogesh Verma, SAC

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