DOCSLIB.ORG

G-Band Waveguide to Microstrip Transition for MMIC Integration

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

Donadio, Oberdan (2012) G-band waveguide to microstrip transition for MMIC integration. PhD thesis. http://theses.gla.ac.uk/3354/ Copyright and moral rights for this thesis are retained by the author A copy can be downloaded for personal non-commercial research or study, without prior permission or charge This thesis cannot be reproduced or quoted extensively from without first obtaining permission in writing from the Author The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the Author When referring to this work, full bibliographic details including the author, title, awarding institution and date of the thesis must be given Glasgow Theses Service http://theses.gla.ac.uk/ [email protected] G-band Waveguide to Microstrip Transition for MMIC Integration by Oberdan Donadio Thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy in the School of Engineering College of Science and Engineering January 2012 Declaration of Authorship I, Oberdan Donadio, declare that this thesis titled, `G-band Waveguide to Microstrip Transition for MMIC Integration' and the work presented in it are my own. I confirm that: This work was done wholly or mainly while in candidature for a research degree at the University of Glasgow. Where any part of this thesis has previously been submitted for a degree or any other qualification at this University or any other institution, this has been clearly stated. Where I have consulted the published work of others, this is always clearly at- tributed. Where I have quoted from the work of others, the source is always given. With the exception of such quotations, this thesis is entirely my own work. I have acknowledged all main sources of help. Where the thesis is based on work done by myself jointly with others, I have made clear exactly what was done by others and what I have contributed myself. Signed: Oberdan Donadio Date: 02/09/2011 i \A smooth sea never made a skillful mariner" (English proverb) Abstract In recent years, Millimetre-Wave (MMW) frequencies (30-300 GHz) have been exploited for a variety of attractive applications such as astronomical observation, medical imag- ing, aircraft aided-control landing, security and concealed weapons detection. All this was also possible thanks to the advances in high frequency circuits where Monolithic Microwave Integrated Circuits (MMICs) represent a key factor. Systems working at MMW often use metal waveguides as interconnect elements and transitions are em- ployed to transfer the signals from these elements to the Radio Frequency (RF) circuits. The objective of this thesis is to design, fabricate and characterise electromagnetic tran- sitions between rectangular waveguide (WR) and planar transmission lines at G-band frequencies (140-220 GHz). The first part of this work presents an overview of the elec- tromagnetic properties of the atmosphere at MMW frequencies and their use for passive MMW imaging applications. Fundamental design concepts and prototypes of real-time imagers are also represented, based on the pioneering work carried out at QinetiQ Ltd. An extensive review of the scientific literature on waveguide transitions presents previous designs and architectures. The work proceeds through design, simulation, fabrication and measurements of G-band transitions highlighting advantages and disadvantages of different structures. The novel design of Elevated E-plane probes, used as waveguide to microstrip transitions in this work, extends the fabrication technique of MMIC air-bridges to build suspended metal structures and provides an additional optimising parameter to improve the reflec- tion performance of the transition by decomposing the substrate influence on the metal probe. The innovative Elevated E-plane probe is fabricated on Semi-Insulated Gallium Arsenide (SI-GaAs) and it is MMIC-integrated, reducing system complexity and optimizing fab- rication and assembly costs. The core of the thesis details the fabrication processes and procedures and a separate section describes the manufacture of G-band rectangular waveguide blocks that host the transitions. The overall fabrication is carried out using in-house facilities at the Univer- sity of Glasgow without the aid of external facilities. Measured results are presented and discussed, validating design and simulations. This work has led to a successful design and fabrication of GaAs-integrated rectangular waveg- uide to microstrip line transition at G-band. Acknowledgements The investigation which is the subject of this Thesis was financially supported by EPSRC and QinetiQ Ltd. and was carried out as CASE award under the terms of QinetiQ Agreement No. 45358. I would like to express my gratitude to my supervisor Dr. Khaled Elgaid for giving me the great opportunity of this Research project at the University of Glasgow and for his insightful guidance and advices throughout its course. I'm also particularly grateful to Dr. Roger Appleby, my industrial supervisor, who gave me the chance to collaborate with QinetiQ and for the fruitful discussions and meetings we had during the course of the project. Thanks to QinetiQ Ltd who contributed to support the research and allowed me to publish its results. Extra special thanks to Prof. Iain Thayne, my second supervisor, for his encouragements and useful feedbacks. I would like to thank Susan Ferguson for introducing me to fabrication, for support and for being always an important source of information when needed. Special thanks to the Ultrafast group and to Helen Mclelland for helping during fabrication processes. Thanks to Wilson MacDougall, from the Mechanical Workshop, for his help in operating the CNC milling machine during the fabrication of my waveguides. I particularly thank Alex Ross for helping me in the substrate thinning and for all the interesting conversations we had. Thank you Alex. No acknowledgement would be complete without mentioning Dr. Gabor Mezosi, whom I thank for sharing his points of view and for his continuous encouragement. He has been a colleague and a precious friend. Thanks to Dr. Michael Strain for his guidance and valuable comments. I wish to thank the wonderful people from the JWNC, they are too many to list but I will remember you all. I also thank all nice friends I had around at the department, Lai Bun, Chi Jeon, Adel, Ian, Antonio, Giuseppe, Carla, Philippe, Giangiacomo, Marc, Corrie, Barry and please forgive me if I forgot someone..... On a personal note, I want to thank my family for supporting me in my choices and for always being there when I needed. Finally, from the bottom of my heart I want to thanks Neus, who has always been by my side and helped me during my hardest moments. I could not have finished this work without her help! Thank you all! iv Publications and Events Aspects of the work described in this Thesis has been published or presented in following papers and internal events: • O. Donadio, K. Elgaid, and R. Appleby, "Waveguide-to-microstrip transition at G-band using Elevated E-plane Probe" Electronics Letters, 47(2), pp.115-116, January 2011. • O. Donadio, K. Elgaid, "Fabrication of Broadband waveguide-to-microstrip tran- sition at G-band", Postgraduate Student Colloquium, University of Glasgow, 2009. • O. Donadio, K. Elgaid, "MMW Waveguide-to-planar Transmission line Design", Postgraduate Student Conference, 1st winner Posters Session, Heriot-Watt Uni- versity Edinburgh, 2008. Contents Declaration of Authorshipi Abstract iii Acknowledgements iv List of Figures ix List of Tables xiii Abbreviations xiv 1 Introduction1 1.1 Introduction...................................1 1.2 An Overview of Millimetre Waves.......................1 1.2.1 Atmospheric Absorption........................2 1.3 Millimetre Wave Imaging...........................6 1.4 Passive Millimetre-Wave (PMMW) Imaging................8 1.4.1 Contrast Model and Materials Properties..............9 1.4.2 System Performance.......................... 12 1.4.3 Different Systems............................ 15 1.5 Trends towards Higher Frequencies...................... 19 1.6 Conclusions................................... 20 2 Rectangular Waveguide to Planar Transmission Line Transitions 21 2.1 Introduction................................... 21 2.2 Aspects of Propagation in Rectangular Waveguide............. 22 2.2.1 Low Loss Transmission Line...................... 22 2.2.2 Rectangular Waveguide Dimensions and Frequency Bands..... 22 2.3 Architecture of the Transitions........................ 22 2.3.1 Ridge-Waveguide Transitions..................... 24 2.3.2 Aperture-coupled Transitions..................... 26 2.3.3 Transversal Transitions........................ 31 2.3.4 In-Line Transitions........................... 35 2.4 Some Considerations.............................. 40 vi Contents vii 2.5 Conclusions................................... 41 3 Design and Methods 45 3.1 Introduction................................... 45 3.2 Electromagnetic Design using EDA Software Packages........... 46 3.2.1 HFSS, FEM and Adaptive Meshing................. 46 3.2.2 Simulation setup............................ 49 3.2.2.1 Materials assignment.................... 49 3.2.2.2 Excitations.......................... 49 3.2.2.3 Boundaries.......................... 50 3.2.2.4 Analysis Setup........................ 50 3.2.2.5 Custom Meshing Operations................ 51 3.3 Design Specifications.............................. 51 3.3.1 Considerations on Design options..................
Recommended publications
  • A Broad Bandwidth Suspended Membrane Waveguide to Thinfilm

    A Broad Bandwidth Suspended Membrane Waveguide to Thinfilm

    A Broad Bandwidth Suspended Membrane Waveguide to Thinfilm Microstrip Transition J. W. Kooi California Institute of Technology, 320-47, Pasadena, CA 91125, USA. C. K. Walker University of Arizona, Dept. of Astronomy. J. Hesler University of Virginia, Dept. of Electrical Engineering. Abstract Excellent progress in the development of Submillimeter-wave SIS and HEB mixers has been demonstrated in recent years. At frequencies below 800 GHz these mixers are typically implemented using waveguide techniques, while above 800 GHz quasi-optical (open structure) methods are often used. In many instances though, the use of waveguide components offers certain advantages. For example, broadband corrugated feed-horns with well defined on axis Gaussian beam patterns. Over the years a number of waveguide to microstrip transitions have been proposed. Most of which are implemented in reduced height waveguide with RF bandwidth less than 35%. Unfortunately reducing the height makes machining of mixer components at terahertz frequencies rather difficult. It also increases RF loss as the current density in the waveguide goes up, and surface finish is degraded. An additional disadvantage of existing high frequency waveguide mixers is the way the active device (SIS, HEB, Schottky diode) is mounted in the waveguide. Traditionally the junction, and its supporting substrate, is mounted in a narrow channel across the guide. This structure forms a partially filled dielectric waveguide, whose dimensions must kept small to prevent energy from leaking out the channel. At frequencies approaching or exceeding a terahertz this mounting scheme becomes impractical. Because of these issues, quasi-optical mixers are typically used at these small wavelength. In this paper, we propose the use of suspended silicon (Si) and silicon nitride (Si3N4) membranes with silicon micro-machined backshort and feedhorn blocks.
  • Optical – Near-Infrared Catalog for the AKARI North Ecliptic Pole Deep field

    Optical – Near-Infrared Catalog for the AKARI North Ecliptic Pole Deep field

    A&A 566, A60 (2014) Astronomy DOI: 10.1051/0004-6361/201322561 & c ESO 2014 Astrophysics Optical – near-infrared catalog for the AKARI north ecliptic pole Deep field Nagisa Oi1, Hideo Matsuhara1, Kazumi Murata1,2, Tomotsugu Goto3, Takehiko Wada1, Toshinobu Takagi1, Youichi Ohyama4, Matthew Malkan5, Myungshin Im6, Hyunjin Shim6,7, Stephen Serjeant8, and Chris Pearson8,9,10 1 Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, 252-5210 Kanagawa, Japan e-mail: [email protected] 2 Department of Space and Astronautical Science, The Graduate University for Advanced Studies, 753-8511 Yamaguchi, Japan 3 Institute of Astronomy and Department of Physics, National Tsing Hua University No. 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan, R.O.C. 4 Academia Sinica, Institute of Astronomy and Astrophysics, 11F of Astronomy-Mathematics Building, National Taiwan University, No.1, Sec. 4, Roosevelt Rd, 10617 Taipei, Taiwan R.O.C. 5 Department of Physics and Astronomy, UCLA, Los Angeles, CA 90095-1547, USA 6 Department of Physics & Astronomy, FPRD, Seoul National University, Shillim-Dong, Kwanak-Gu, 151-742 Seoul, Korea 7 Department of Earth Science Education, Kyungpook National University, 702-701 Daegu, Republic of Korea 8 Astrophysics Group, Department of Physics, The Open University, Milton Keynes, MK7 6AA, UK 9 RAL Space, Rutherford Appleton Laboratory, Harwell Oxford, OX11 0QZ, UK 10 Oxford Astrophysics, Oxford University, Keble Road, Oxford OX1 3RH, UK Received 29 August 2013 / Accepted 18 March 2014 ABSTRACT ∗ Aims. We present an 8-band (u , g , r , i , z , Y, J, Ks) optical to near-infrared deep photometric catalog based on the observations made with MegaCam and WIRCam at the CFHT, and compute photometric redshifts, zp in the north ecliptic pole (NEP) region.
  • A Survey on Microstrip Patch Antenna Using Metamaterial Anisha Susan Thomas1, Prof

    A Survey on Microstrip Patch Antenna Using Metamaterial Anisha Susan Thomas1, Prof

    ISSN (Print) : 2320 – 3765 ISSN (Online): 2278 – 8875 International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering (An ISO 3297: 2007 Certified Organization) Vol. 2, Issue 12, December 2013 A Survey on Microstrip Patch Antenna using Metamaterial Anisha Susan Thomas1, Prof. A K Prakash2 PG Student [Wireless Technology], Dept of ECE, Toc H Institute of Science and Technology, Cochin, Kerala, India 1 Professor, Dept of ECE, Toc H Institute of Science and Technology, Cochin, Kerala, India 2 ABSTRACT: Microstrip patch antennas are used for mobile phone applications due to their small size, low cost, ease of production etc. The MSA has proved to be an excellent radiator for many applications because of its several advantages, but it also has some disadvantages. Lower gain and narrow bandwidth are the major drawbacks of a patch antenna. In this paper, a survey on the existing solutions for the same which are developed through several years and an evolving technology metamaterial is presented. Metamaterials are artificial materials characterized by parameters generally not found in nature, but can be engineered. They differ from other materials due to the property of having negative permeability as well as permittivity. Metamaterial structure consists of Split Ring Resonators (SRRs) to produce negative permeability and thin wire elements to generate negative permittivity. Performance parameters especially bandwidth, of patch antennas which are usually considered as narrowband antennas can be improved using metamaterial. Metamaterials are also the basis of further miniaturization of microwave antennas. Keywords: Microstrip antenna, Metamaterial, Split Ring Resonator, Miniaturization, Narrowband antennas. I. INTRODUCTION Although the field of antenna engineering has a history of over 80 years it still remains as described in [1] “….
  • New Journal of Physics the Open–Access Journal for Physics

    New Journal of Physics the Open–Access Journal for Physics

    New Journal of Physics The open–access journal for physics On the origin of the fast photoluminescence band in small silicon nanoparticles J Valenta1,6, A Fucikova1, I Pelant2,KKusová˚ 2, K Dohnalová2, A Aleknaviciusˇ 2,5, O Cibulka2, A Fojtík3 and G Kada4 1 Department of Chemical Physics and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Prague 2, Czech Republic 2 Institute of Physics, Academy of Sciences of the Czech Republic, v. v. i., Cukrovarnická 10, 162 53 Prague 6, Czech Republic 3 Faculty of Nuclear Science and Physical Engineering, Czech Technical University in Prague, V Holesoviˇ ckáchˇ 2, 182 00 Praha 8, Czech Republic 4 Agilent Technologies, Mooslackengasse 17, 1190 Vienna, Austria E-mail: [email protected] New Journal of Physics 10 (2008) 073022 (6pp) Received 13 February 2008 Published 11 July 2008 Online at http://www.njp.org/ doi:10.1088/1367-2630/10/7/073022 Abstract. Colloidal suspensions of small silicon nanoparticles (diameter around 2 nm) with fast and efficient ultraviolet–blue photoluminescence (PL) band are fabricated by enhanced electrochemical etching of Si wafers. The detailed study of photoluminescence excitation spectra in a wide range of excitation photon energies (270–420 nm) reveals specific behavior of the Stokes shift of the fast PL band that agrees well with theoretical calculation of optical transitions in small silicon nanocrystals and is distinct from emission of silicon dioxide defects. Efficient photoluminescence (PL) of porous silicon (PSi)—first observed by Canham [1]— provoked intensive research on silicon-based nanocrystalline materials. There are mainly two types of PL emission in Si nanostructures at room temperature.
  • The UKIRT Infrared Deep Sky Survey ZY JHK Photometric System: Passbands and Synthetic Colours

    The UKIRT Infrared Deep Sky Survey ZY JHK Photometric System: Passbands and Synthetic Colours

    Mon. Not. R. Astron. Soc. 367, 454–468 (2006) doi:10.1111/j.1365-2966.2005.09969.x The UKIRT Infrared Deep Sky Survey ZY JHK photometric system: passbands and synthetic colours P. C. Hewett,1⋆ S. J. Warren,2 S. K. Leggett3 and S. T. Hodgkin1 1Institute of Astronomy, Madingley Road, Cambridge CB3 0HA 2Blackett Laboratory, Imperial College of Science, Technology and Medicine, Prince Consort Road, London SW7 2AZ 3United Kingdom Infrared Telescope, Joint Astronomy Centre, 660 North A‘ohoku Place, Hilo, HI 96720, USA Accepted 2005 December 7. Received 2005 November 28; in original form 2005 September 16 ABSTRACT The United Kingdom Infrared Telescope (UKIRT) Infrared Deep Sky Survey is a set of five surveys of complementary combinations of area, depth and Galactic latitude, which began in 2005 May. The surveys use the UKIRT Wide Field Camera (WFCAM), which has a solid angle of 0.21 deg2. Here, we introduce and characterize the ZY JHK photometric system of the camera, which covers the wavelength range 0.83–2.37 µm. We synthesize response functions for the five passbands, and compute colours in the WFCAM, Sloan Digital Sky Survey (SDSS) and two-Micron All Sky Survey (2MASS) bands, for brown dwarfs, stars, galaxies and quasars of different types. We provide a recipe for others to compute colours from their own spectra. Calculations are presented in the Vega system, and the computed offsets to the AB system are provided, as well as colour equations between WFCAM filters and the SDSS and 2MASS passbands. We highlight the opportunities presented by the new Y filter at 0.97–1.07 µm for surveys for hypothetical Y dwarfs (brown dwarfs cooler than T), and for quasars of very high redshift, z > 6.4.
  • 1 Distinct Band Reconstructions in Kagome Superconductor Csv3sb5

    1 Distinct Band Reconstructions in Kagome Superconductor Csv3sb5

    Distinct band reconstructions in kagome superconductor CsV3Sb5 Yang Luo1,#, Shuting Peng1,#, Samuel M. L. Teicher2,#, Linwei Huai1,#, Yong Hu1,3, Brenden R. Ortiz2, Zhiyuan Wei1, Jianchang Shen1, Zhipeng Ou1, Bingqian Wang1, Yu Miao1, Mingyao Guo1, M. Shi3, Stephen D. Wilson2 and J.-F. He1,* 1Hefei National Laboratory for Physical Sciences at the Microscale, Department of Physics and CAS Key Laboratory of Strongly-coupled Quantum Matter Physics, University of Science and Technology of China, Hefei, Anhui 230026, China 2Materials Department and California Nanosystems Institute, University of California Santa Barbara, Santa Barbara, California 93106, USA 3Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland #These authors contributed equally to this work. *To whom correspondence should be addressed: [email protected] The new two-dimensional (2D) kagome superconductor CsV3Sb5 has attracted much recent attention due to the coexistence of superconductivity, charge order, topology and kagome physics [1- 33]. A key issue in this field is to unveil the unique reconstructed electronic structure, which successfully accommodates different orders and interactions to form a fertile ground for emergent phenomena. Here, we report angle-resolved photoemission spectroscopy (ARPES) evidence for two distinct band reconstructions in CsV3Sb5. The first one is characterized by the appearance of new electron energy band at low temperature. The new band is theoretically reproduced when the three dimensionality of the charge order [21-23] is considered for a band-folding along the out-of-plane direction. The second reconstruction is identified as a surface induced orbital-selective shift of the electron energy band. Our results provide the first evidence for the three dimensionality of the charge order in single-particle spectral function, highlighting the importance of long-range out-of-plane electronic correlations in this layered kagome superconductor.
  • NLTE Solar Irradiance Modeling with the COSI Code

    NLTE Solar Irradiance Modeling with the COSI Code

    Astronomy & Astrophysics manuscript no. Irradiance˙COSI c ESO 2018 August 12, 2018 NLTE solar irradiance modeling with the COSI code A. I. Shapiro1, W. Schmutz1, M. Schoell1,2, M. Haberreiter3, and E. Rozanov1,4 1 Physikalisch-Meteorologishes Observatorium Davos, World Radiation Center, 7260 Davos Dorf, Switzerland e-mail: [email protected] 2 Institute for Astronomy ETH, Zurich, Switzerland 3 Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA 4 Institute for Atmospheric and Climate science ETH, Zurich, Switzerland Received 30 December 2009; accepted 29 March 2010 ABSTRACT Context. The solar irradiance is known to change on time scales of minutes to decades, and it is suspected that its substantial fluctua- tions are partially responsible for climate variations. Aims. We are developing a solar atmosphere code that allows the physical modeling of the entire solar spectrum composed of quiet Sun and active regions. This code is a tool for modeling the variability of the solar irradiance and understanding its influence on Earth. Methods. We exploit further development of the radiative transfer code COSI that now incorporates the calculation of molecular lines. We validated COSI under the conditions of local thermodynamic equilibrium (LTE) against the synthetic spectra calculated with the ATLAS code. The synthetic solar spectra were also calculated in non-local thermodynamic equilibrium (NLTE) and compared to the available measured spectra. In doing so we have defined the main problems of the modeling, e.g., the lack of opacity in the UV part of the spectrum and the inconsistency in the calculations of the visible continuum level, and we describe a solution to these problems.
  • Raman Spectroscopy of Graphene and the Determination of Layer Thickness

    Raman Spectroscopy of Graphene and the Determination of Layer Thickness

    Application Note: 52252 The Raman Spectroscopy of Graphene and the Determination of Layer Thickness Mark Wall, Ph.D., Thermo Fisher Scientific, Madison, WI, USA Currently, a tremendous amount of activity is being directed Key Words towards the study of graphene. This interest is driven by the novel properties that graphene possesses and its potential • DXR Raman for use in a variety of application areas that include but Microscope are not limited to: electronics, heat transfer, bio-sensing, • 2D Band membrane technology, battery technology and advanced composites. Graphene exists as a transparent two dimen- • D Band sional network of carbon atoms. It can exist as a single • G Band atomic layer thick material or it can be readily stacked to form stable moderately thick samples containing millions • Graphene of layers, a form generally referred to as graphite. The • Layer Thickness interesting properties exhibited by graphene (exceptionally large electrical and thermal conductivity, high mechanical strength, high optical transparency, etc…), however, are only observed for graphene films that contain only one or a few layers. Therefore, developing technologies and devices based upon graphene’s unusual properties requires within the carbon lattice are present). These differences, accurate determination of the layer thickness for materials although they appear subtle, supply very important infor- under investigation. Raman spectroscopy can be employed mation when scrutinized closely. There are differences in to provide a fast, non destructive means of determining the band positions and the band shapes of the G band layer thickness for graphene thin films. 2D bands and the relative intensity of these bands are also significantly different.
  • The Origin of UV / Optical Variability of AGN: Relationship to X-Ray Variability

    The Origin of UV / Optical Variability of AGN: Relationship to X-Ray Variability

    The origin of UV / Optical Variability of AGN: Relationship to X-ray Variability Ian McHardy University of Southampton 1 Southampton Main Questions • What drives UV/optical variability in AGN? • How is the X-ray band related to UV/optical? • What do X-ray/UV/optical variations tell us about AGN inner structure? 2 Southampton Possible drivers of UV/optical Variability - Reprocessing of higher energy photons - which “high” energy? X-ray? Far-UV? - reprocessing off what? Disc? BLR? - Intrinsic disc variations 3 Southampton Observational Diagnostics • Reprocessing - High energies lead uv/optical by short (hour-days) light travel time. Allows ‘reverberation’ mapping of reprocessing structures. Measure lag from different temperature regions (different λ ). • Intrinsic disc variability – High energies lag: two possibilities – Long lag (months), viscous propagation timescale for perturbations to reach X-ray region from optical in disc – Short lag (hour-day), light travel time of UV seed photons to corona 4 REPROCESSING Southampton Wavelength dependence of lags For standard Shakura-Sunyaev DISC, 4 −1 −3 L(R)=σT ∝MBH . m! E R dissipating gravitational potential energy ! ( R in gravitational radii) −1/4 1/4 −3/4 i.e. T ∝ M m! R BH E Disc illumination from point source, height H above disc, also falls off as H R-3 So for reprocessing 4/3 Lag ∝Wavelength (eg Cackett et al 2007) from disc, we expect and Lag ∝M2/3m! 1/3 ! E For illumination of a shell-type structure, eg the BLR or torus, Illumination falls of as R-2 giving Lag ∝Wavelength2 5 Southampton
  • A Simple Approach for Designing a Filter on Microstrip Lines

    A Simple Approach for Designing a Filter on Microstrip Lines

    Applied Engineering Letters Vol.4, No.1, 19-23 (2019) e-ISSN: 2466-4847 A SIMPLE APPROACH FOR DESIGNING A FILTER ON MICROSTRIP LINES UDC: 621.372.543 Original scientific paper https://doi.org/10.18485/aeletters.2019.4.1.3 Ashish Kumar1 1Aryabhatta research institute of observational sciences (ARIES), Nainital, India Abstract: ARTICLE HISTORY This paper deals with the design and fabrication of edge-coupled band pass Received: 22.03.2019. filter (BPF) circuit (fifth order) on microwave laminate for 4.5 GHz ± 0.5 GHz Accepted: 26.03.2019. application. The design of filter is realized on a high quality RT/ duroid Available: 31.03.2019. laminate having the dielectric constant 10.5 and substrate thickness 1.27 mm. The relevant design specifications, simulation, and test results of the circuit is described. The numerical calculations and simulations are KEYWORDS performed in Linpar. The Printed Circuit Board (PCB) artwork is prepared in filter, microstrips, edge- coupled, linpar, CorelDraw, CorelDraw. A prototype of the design was manufactured and tested on microwave microwave network analyzer. Some offsets are observed between the theoretical and practical results, which may be attributed to the wide tolerance in the dielectric permittivity specified for the RT/ duroid substrate. 1. INTRODUCTION certain complexities. However, without entering into any design complexities, the present work is In electronic circuits, the filter is a network focussed on the basic steps involved in the design having non-uniform frequency response and fabrication of an edge-coupled BPF on characteristics in the desired frequency range. microstrip lines. Following the steps, one can They are used to manipulate the signal by realize any other microwave filters for their enhancing or attenuating certain frequency ranges frequency band of interests.
  • RF / Microwave PC Board Design and Layout

    RF / Microwave PC Board Design and Layout

    RF / Microwave PC Board Design and Layout Rick Hartley L-3 Avionics Systems [email protected] 1 RF / Microwave Design - Contents 1) Recommended Reading List 2) Basics 3) Line Types and Impedance 4) Integral Components 5) Layout Techniques / Strategies 6) Power Bus 7) Board Stack-Up 8) Skin Effect and Loss Tangent 9) Shields and Shielding 10) PCB Materials, Fabrication and Assembly 2 RF / Microwave - Reading List PCB Designers – • Transmission Line Design Handbook – Brian C. Wadell (Artech House Publishers) – ISBN 0-89006-436-9 • HF Filter Design and Computer Simulation – Randall W. Rhea (Noble Publishing Corp.) – ISBN 1-884932-25-8 • Partitioning for RF Design – Andy Kowalewski - Printed Circuit Design Magazine, April, 2000. • RF & Microwave Design Techniques for PCBs – Lawrence M. Burns - Proceedings, PCB Design Conference West, 2000. 3 RF / Microwave - Reading List RF Design Engineers – • Microstrip Lines and Slotlines – Gupta, Garg, Bahl and Bhartia. Artech House Publishers (1996) – ISBN 0-89006-766-X • RF Circuit Design – Chris Bowick. Newnes Publishing (1982) – ISBN 0-7506-9946-9 • Introduction to Radio Frequency Design – Wes Hayward. The American Radio Relay League Inc. (1994) – ISBN 0-87259-492-0 • Practical Microwaves – Thomas S. Laverghetta. Prentice Hall, Inc. (1996) – ISBN 0-13-186875-6 4 RF / Microwave Design - Basics ) RF and Microwave Layout encompasses the Design of Analog Based Circuits in the range of Hundreds of Megahertz (MHz) to Many Gigahertz (GHz). ) RF actually in the 500 MHz - 2 GHz Band. (Design Above 100 MHz considered RF.) ) Microwave above 2 GHZ. 5 RF / Microwave Design - Basics ) Unlike Digital, Analog Signals can be at any Voltage and Current Level (Between their Min & Max), at any point in Time.
  • Tests of Microstrip Dispersion Formulas Presentation to Bring Them Into a Similar Formalism for Compari­ £ E(O) Is the Zero-Frequency, Or H

    Tests of Microstrip Dispersion Formulas Presentation to Bring Them Into a Similar Formalism for Compari­ £ E(O) Is the Zero-Frequency, Or H

    IEFF. TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 36, No.3, MARCH 1988 619 The most restrictive convergence plot is usually the one for the ranged from 2.3 percent to 4.1 percent of the seven formulas for <,,(j) propagation constant of the narrowest strip spacing at the lowest tested. A formula due to Kirschning and Jansen (10( showed the lowest frequency. This is due to the field having least space in terms of average deviation from measured values, although the differences between the predictions of their formuIa and others tested are of the order of the wavelength to adjust to the structure. However, when the odd error limits of the comparison process. It is concluded that the results mode is weakly bound at high frequencies, a small change in the indicate the suitability of relatively simple analytical expressons for the propagation constant changes the decay rate away from the strips computation for microstrip dispersion. dramatically. This greatly &ffects the power contained in the mode and hence the characteristic impedance. In this case the I. INTRODUCTION odd-mode impedance at high frequencies sets the number of modes required. Generally, there exists a relation between the The widespread use of micros trip transmission line for micro­ number of modes and the £2/£1 = £2/£3 dielectric step. Larger wave circuit construction has created a need for accurate and steps require more modes since the field has a more complicated practical computational algorithms for the values of microstrip structure in which to conform. line parameters. For this purpose, the micros trip line is modeled Numerical instabilities occur in the determinant calculation for as an equivalent TEM system at the operating frequency.