DOCSLIB.ORG

Future Array Design & Technology

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Future Array Design & Technology Future Array Design & Technology Tony Beasley (NRAO) Fifteenth Synthesis Imaging Workshop 1-8 June 2016 Future Array Design & Technology • Short history of radio astronomy • Review of current/planned telescopes • Leading-edge technologies Electromagnetic Radiation • Varying physical properties – temperature, pressure, structure, magnetic fields yield different EM emissions • Radio – non-thermal acceleration of charged particles, spiraling in magnetic field, thermal emission • Atoms & molecules – also possess unique radio frequencies Heinrich Hertz: 1888 – early radio transmission Radio Emission from Sun? Edison (1890), Lodge (1897) …. Wilsing & Scheiner 1896 Nordman 1900 • All unsuccessful at e.g. detecting Sun… • Planck – estimates Solar thermal radiation small • Heaviside – Kennelly – ionosphere optically thick • No attempts for 30 years… • 1930’s – transatlantic radio phone calls • Interference: 15-30m wavelengths • Bell Labs – Karl Jansky, engineer Karl Jansky Karl Jansky & Grote Reber • Detected radio signals 1932 – Nearby thunderstorms – Distant thunderstorms – Faint steady hiss ??? • Sidereal, not solar plane of our Galaxy • 1933 May 5 – NY Times announcement • Jansky wanted to do more – Bell labs didn’t… Grote Reber WWII • Large resources put into radio, radar technology worldwide • During war: J.S. Hey (UK) finally discovered radio emission from the Sun, also Australian/NZ group (early morning jamming..) • After war: UK, Australia, Netherlands moved expertise and resources in “radio astronomy” • US – Caltech/Owens Valley in 1950s • National Radio Astronomy Observatory - 1956 Jodrell Telescope NRAO 300’ Parkes Telescope Effelsberg Radio Telescope Arecibo Observatory Green Bank Telescope Shanghai Tian Ma 65m Angular Resolution Resolving power (how small of a thing you can “see”) depends on the size of the telescope and the wavelength of the light For radio waves, l this is large… size So this must also be large “Size” = diameter of telescope for single dish; maximum distance between telescopes for arrays Radio Telescopes: Resolution Size Size Single Dish Arrays Interferometer Correlator ……Reconfigurable Early interferometers - Cambridge, UK Cambridge 1mile & 4C Telescopes Westerbork Synthesis Radio Telescope Very Large Array Australia Telescope Compact Array Allen Telescope Array Very Long Baseline Array Space VLBI RadioAstron Atmosphere Low Frequency? LOFAR Long Wavelength Array Murchison Widefield Array PAPER HERA High Frequency? South Pole Telescope Submillimeter Array Atacama Large Millimeter/submm Array - ALMA Space? Radio Telescopes Around the World WMAP (23-94 GHz) Planck (100-857 GHz) Herschel (>480 GHz) Wilkinson Microwave Anisotropy Probe (WMAP) WK--bandband 2394 GHzGHz Background=3 K blackbody radiation map.gsfc.nasa.gov Wikipedia: # Radio Telescopes >> 100 Square Kilometer Array SKA Components • SKA-low – ~80-300 MHz, primarily Epoch of Reionization • SKA-mid – ~300 MHz-few GHz, primarily galaxy evolution (HI telescope) and Dark Energy; also gravity – Note: 1 km2 is nearly 6000 15m dishes!! • SKA-high – Few GHz to 25-50 GHz, primarily cradle of life (star and planet formation, galaxy formation) • Phase 1 (first 10%) followed by Phase 2. Cosmic Dawn (First Testing General Relativity Stars and Galaxies) (Strong Regime, Gravitational Waves) Galaxy Evolution (Normal Galaxies z~2-3) Cradle of Life (Planets, Molecules, SETI) Cosmology (Dark Matter, Large Scale Structure) Cosmic Magnetism (Origin, Evolution) Exploration of the Unknown Summary of the SKA Baseline Design 250,000 element 2020 96 survey enabled dishes : Low Frequency Aperture Array I se ha P 254 dishes 2024 >250,000 element Mid Frequency Aperture : Low Frequency Aperture Array Array II se ha P 2500 dishes Cosmic Dawn & Reionization Cosmology & Pulsars Cosmic Magnetism Cradle of Life Galaxy Evolution ce ien Sc 50 MHz 100 MHz 1 GHz 10 GHz SKA1-LOW:Australia ~130,000 antennas then 500,000 in Phase 2 Footer text SKA1-MID: Africa 200 15-m dishes across 150 km ~2,000 dishes in Phase 2, across southern Africa Footer text Sensitivity Comparison Image Quality Comparison “Structural” dynamic range of ~1000:1 rather than ~3:1 per VLA track (eg. SKA1-Mid vs. VLA A-config.) Image Quality Comparison Single SKA1-Low track compared to LOFAR-INTL Central SKA2 South Africa Core Site: Potential Dish Array Transition from SKA1 (red) to SKA2 (blk) Footer text SKA Organisation: 10 countries Observers: • France • Germany • Japan Australia (DoI&S) • Malta Canada (NRC-HIA) • Portugal China (MOST) • Spain India (DAE) • Korea Italy (INAF) • USA Netherlands (NWO) New Zealand (MED) Contacts: South Africa (DST) • Brazil Sweden (Chalmers) • Ireland UK (STFC) • Russia • Switzerlan SKA HQ: Jodrell Bank, UKSKA HQ – Jodrell Bank, UK Australian SKA Prototype (ASKAP) MeerKAT Precursor progress: MeerKAT • Effective area 10x JVLA, ALMA, located in US Southwest • Frequency range: 1 – 50, 70 – 115 GHz • ~18m antennas w. 50% to few km + 40% to 50km + 10% to 3000km? • Design goal: minimize mass production and operations costs Thermal Imaging on Milliarcsecond Scales HL Tau – ALMA B6 Planet Formation on Milliarcsecond scales Kraus et al. 2014 ngVLA: Terrestrial zone ALMA 250GHz Brogan ea. planet formation imager • Protoplantary disks: Inner ~ 20AU disk 100AU optically thick in mm/submm 0.7” at • Grain growth and stratification: from dust 140pc to pebbles to planets • Simulation Jupiter at 13AU, Saturn at 6AU Image both gaps + annual motions Circumplanetary disks: planet accretion! ngVLA 100hr 25GHz 0.1” = 10mas 13AU model model rms = 90nJy/bm = 1K ngVLA ngVLA CHIME Five hundred meter Aperture Spherical Telescope FAST Technology Challenges • Antennas – cheap, mass production, low maintenance, accurate • Receivers – mass production, Phased Array Feeds, wide bandwidths • Cryogenics – large operations costs • Data transport – costs for high bandwidth backhaul • Correlators – scale, power • Data Management – PB, EB of data to be stored, processed – sometimes in real time… • Software/Processing • Access to next generation of scientists/engineers – you!! SKA Mid MeerKAT 15-m dish 13.5-m dish 32 tons 47 tons Phased Array Feeds Data Management Global Software Infrastructure Summary • Many large radio interferometers operating/planned. • All facing growing challenges of data scale and complexity. • SKA and ngVLA – major challenges. • Scientifically exciting future for radio interferometry ahead! Need a few (thousand) good people. 88 www.nrao.edu science.nrao.edu The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc..
Load more

Recommended publications
  • Multidisciplinary Use of the J Very Long Baseline Array
    PE84-16~690 Multidisciplinary Use of the j Very Long Baseline Array Proceedings of a Workshop REPRODUCED BY NATIONAL TECHNICAL NAS INFORMATION SERVICE us DEPAR1MENl OF COMMERCE NAE .. SPRINGFiElD, VA. 22161 10M 50272 ·101 REPORT DOCUMENTATION \1. REPORT NO. PAGE 4. TItle end Subtitle 50 Report Dete Multidisciplinary Use of the Very Long Baseline Array .. Februarv 1984 7. Author(l) L Performln. O...nlutlon Rept. No. 9. Performlna O...nlutlon Neme end Add.... 10. ProJKt/Tuk/Wort! Unit No. National Research Council 11. Contrect(C2 or Gr.nt(G) No. Commission on Physical Sciences, Mathematics, and DMA800-M0366/P Resources ~MDA903-83-M-5896/P i (G)AST-8303119 2101 Constitution Avenue, Washington, DC 20418 ~NA 83AAA02632/P 12. Sponsor1na O..enlutlon Neme end Add_ 11. Type of Report & Period Covered National Science Foundation Final Report. National Aeronautics and Space Administration 11/01/82-3/31/84 Defense Mapping Agency 14. NOAA National Geodetic Survev , Defense Adv. Res. Proj. 15. Supplementer)' Notes . Agency 16. Abltreet (Umlt 200 words) The National Research Council organized a workshop to gather together experts in very long baseline interferometry, astronomy, space navigation, general relativity and the earth sciences,. The purpose of the workshop was to provide a forum for consideration of the various possible multi­ disciplinary uses of the very long baseline array. Geophysical investigations received major attention. Geodesic uses of the very long baseline array were identified as were uses for fundamental astronomy investigations. Numerous specialized uses were identified. i, Document Anelysll e. Descriptors Very Long Baseline Array, astronomical research, space navigation, general relativity, geophysics, earth sciences, geodetic monitoring.
    [Show full text]
  • Radio Astronomy & Radio Telescopes
    Radio Astronomy & Radio Telescopes Tasso Tzioumis ([email protected]) Australia Telescope National Facility (ATNF) sms2020, Stellenbosch 2-6 March 2020 CSIRO ASTRONOMY AND SPACE SCIENCE Radio Astronomy – ITU definition 1.13 radio astronomy: Astronomy based on the reception of radio waves of cosmic origin. 1.5 radio waves or hertzian waves: Electromagnetic waves of frequencies arbitrarily lower than 3 000 GHz, propagated in space without artificial guide. • Astronomy covers the whole electromagnetic spectrum • Radio astronomy is the “low energy” part of the spectrum é 3 000 GHz Radioastronomy & Radio telescopes | Tasso Tzioumis Radio Astronomy “special” characteristics Technical challenges • Very faint signals – measured in 10-26 W/m2/Hz (-260 dBW) • “Power collected by all radiotelescopes since the start of radio astronomy would light a 1W bulb for less than 1 second” • à Need “sensitivity” i.e. large antennas and/or arrays of many antennas • à Very susceptible to intereference • Celestial structures at all scales: from very large to very small • à Need “spatial resolution” i.e. ability to see the details at all scales • à Need large antennas and/or arrays of many antennas • Astronomical events at all timescales(from < 1ms to > millions years) & and at all spectral resolutions (from < 1 Hz to GHz) • à Need very high time and frequency resolution • à Sensitive telescopes and arrays & extreme technical challenges Radioastronomy & Radio telescopes | Tasso Tzioumis Radio Astronomy “special” characteristics Scientific challenges • Radio
    [Show full text]
  • List of Acronyms
    List of Acronyms List of Acronyms AAS American Astronomical Society AC (IVS) Analysis Center ACF AutoCorrelation Function ACU Antenna Control Unit ADC Analog to Digital Converter AES Advanced Engineering Services Co., Ltd (Japan) AGILE Astro-rivelatore Gamma ad Immagini LEggero satellite (Italy) AGN Active Galactic Nuclei AIPS Astronomical Image Processing System AIUB Astronomical Institute, University of Bern (Switzerland) AO Astronomical Object APSG Asia-Pacific Space Geodynamics program APT Asia Pacific Telescope ARIES Astronomical Radio Interferometric Earth Surveying program ASD Allan Standard Deviation ASI Agenzia Spaziale Italiana (Italy) ATA Allen Telescope Array (USA) ATCA Australia Telescope Compact Array (Australia) ATM Asynchronous Transfer Mode ATNF Australia Telescope National Facility (Australia) AUT Auckland University of Technology (New Zealand) A-WVR Advanced Water Vapor Radiometer BBC Base Band Converter BdRAO Badary Radio Astronomical Observatory (Russia) BIPM Bureau Internacional de Poids et Mesures (France) BKG Bundesamt f¨ur Kartographie und Geod¨asie (Germany) BMC Basic Module of Correlator BOSSNET BOSton South NETwork BVID Bordeaux VLBI Image Database BWG Beam WaveGuide CARAVAN Compact Antenna of Radio Astronomy for VLBI Adapted Network (Japan) CAS Chinese Academy of Sciences (China) CASPER Center for Astronomy Signal Processing and Electronics Research (USA) CAY Centro Astron´omico de Yebes (Spain) CC (IVS) Coordinating Center CDDIS Crustal Dynamics Data Information System (USA) CDP Crustal Dynamics Project CE
    [Show full text]
  • Short History of Radio Astronomy Jansky – January 1932
    Short History of Radio Astronomy Jansky – January 1932 Modified Bruce Array: Harald Friis design December 1932 Jansky’s 1932 Data Grote Reber- 1937 9.5 m Parabolic Reflector! Strip Chart output From Strip Chart to Contour Plot… 1940 Ap. J. paper…barely Reber’s 160 MHz contour map published in the ApJ in 1944. This shows the northern sky in equatorial coordinates. The Reber’s 160 MHz contour map published in the ApJ in 1944. This shows the northern sky in equatorial coordinates. The Reber’s 160 MHz contour map published in the ApJ in 1944. This shows the northern sky in equatorial coordinates. The Reber’s 160 MHz contour map published in the ApJ in 1944. This shows the northern sky in equatorial coordinates. The Jan Oort & Hendrik van de Hulst Lieden Observatory 1944 Predicted HI Line Detection of Hydrogen Line …… Ewen & Purcell 21 cm HI Line (1420 MHz) Purcell HI Receiver: Doc Ewen (1951) Milky Way in Optical Origin of SETI Nature, 1959 Philip Morrison 1959 Project Ozma: April 6, 1960 Tau Ceti & Epsilon Eridani Cosmic Background: Penzias & Wilson 1965 • 20 ft Echo Horn (Sugar Scoop): • Harald Friis design Pulsars: Bell and Hewish 1967 Detection of Pulsars: ~100ft of chart/day Chart recording of the pulsar Examples of scintillating detection and an interference signal somewhat later in time. Fast chart recording of pulsar emission (LGM nomenclature is “Little Green Arecibo Message: 1974 Big Ear Radio Telescope OSU Wow! Signal, Aug. 15, 1977 Sagitarius, Chi Sagittari star group NRAO 36ft Kitt Peak Telescope The Drake Equation The Drake equation
    [Show full text]
  • 390 the VERY LONG BASELINE ARRAY PETER J. NAPIER National
    Radio Interferomelry: Theory, Techniques and Applications, 390 IAU Coll. 131, ASP Conference Series, Vol. 19,1991, T.J. Comwell and R.A. Perley (eds.) THE VERY LONG BASELINE ARRAY PETER J. NAPIER National Radio Astronomy Observatory, P.O.Box 0, Socorro, NM 87801, USA ABSTRACT The Very Long Baseline Array, currently under construction, is a dedicated VLBI array consisting of ten 25m diameter antennas and a 20 station correlator. The key design features that make it a flexible, general purpose instrument are reviewed and some details are provided of the array layout, frequency coverage and sensitivity. INTRODUCTION Construction of the Very Long Baseline Array (VLBA) began in 1985 and is scheduled for completion in 1992. The goal of the project is to provide an instrument which can carry out research on a wide range of problems in the field of very high resolution radio astronomy. General information about the VLBA and its potential research areas is available in Kellerman and Thompson (1985) and a summary of its instrumental parameters is provided by Vanden Bout (1991). In this paper we briefly review the current major design goals for the instrument and give some details of the array layout and antenna and receiver performance. Details of other aspects of the VLBA can be found elsewhere in these proceedings; see Rogers (tape recorder), Bagri and Thompson (electronics design), Thompson and Bagri (calibration system) and Chikada (correlator). PROJECT DESIGN GOALS The principal design goals for the VLBA are as follows: (1) Provide an array of 10 identical elements dedicated to VLBI astronomy. The antennas will be in continuous operation under remote control from the Array Operations Center (AOC) in Socorro.
    [Show full text]
  • (LWA): a Large HF/VHF Array for Solar Physics, Ionospheric Science, and Solar Radar
    The Long Wavelength Array (LWA): A Large HF/VHF Array for Solar Physics, Ionospheric Science, and Solar Radar A Ground-Based Instrument Paper for the 2010 NRC Decadal Survey of Solar and Space Physics Lee J Rickard, Joseph Craig, Gregory B. Taylor, Steven Tremblay, and Christopher Watts University of New Mexico, Albuquerque, NM 87131 Namir E. Kassim, Tracy Clarke, Clayton Coker, Kenneth Dymond, Joseph Helmboldt, Brian C. Hicks, Paul Ray, and Kenneth P. Stewart Naval Research Laboratory, Washington, DC 20375 Jacob M. Hartman NRC Research Associate, in residence at Naval Research Laboratory Stephen M. White AFRL, Kirtland AFB, Albuquerque, NM 87117 Paul Rodriguez Consultant, Washington, DC 20375 Steve Ellingson and Chris Wolfe Virginia Tech, Blacksburg, VA 24060 Robert Navarro and Joseph Lazio NASA Jet Propulsion Laboratory, Pasadena, CA 91109 Charles Cormier and Van Romero New Mexico Institute of Mining & Technology, Socorro, NM 87801 Fredrick Jenet University of Texas, Brownsville, TX 78520 and the LWA Consortium Executive Summary The Long Wavelength Array (LWA), currently under construction in New Mexico, will be an imaging HF/VHF interferometer providing a new approach for studying the Sun-Earth environment from the surface of the sun through the Earth’s ionosphere [1]. The LWA will be a powerful tool for solar physics and space weather investigations, through its ability to characterize a diverse range of low- frequency, solar-related emissions, thereby increasing our understanding of particle acceleration and shocks in the solar atmosphere along with their impact on the Sun-Earth environment. As a passive receiver the LWA will directly detect Coronal Mass Ejections (CMEs) in emission, and indirectly through the scattering of cosmic background sources.
    [Show full text]
  • Draft Environmnetal Impact Statement for the Green Bank Observatory
    Draft November 9, 2017 Draft Environmental Impact Statement for the Green Bank Observatory, Green Bank, West Virginia National Science Foundation November 9, 2017 Cover Sheet Draft Environmental Impact Statement Green Bank Observatory, Green Bank, West Virginia Responsible Agency: The National Science Foundation (NSF) For more information, contact: Ms. Elizabeth Pentecost Division of Astronomical Sciences Room W9152 2415 Eisenhower Avenue Alexandria, VA 22314 Public Comment Period: November 9, 2017 through January 8, 2018 (extended beyond typical 45-day review period to allow for the holidays) To Submit a Comment: • Send email with subject line “Green Bank Observatory” to: [email protected] • Send mail addressed to: Ms. Elizabeth Pentecost, RE: Green Bank Observatory Division of Astronomical Sciences Room W9152 2415 Eisenhower Avenue Alexandria, VA 22314 Abstract: The NSF has produced a Draft Environmental Impact Statement (DEIS) to analyze the potential environmental impacts associated with potential funding changes for Green Bank Observatory in Green Bank, West Virginia. The five Alternatives analyzed in the DEIS are: A) collaboration with interested parties for continued science- and education-focused operations with reduced NSF funding (the Agency- preferred Alternative); B) collaboration with interested parties for operation as a technology and education park; C) mothballing of facilities; D) demolition and site restoration; and the No-Action Alternative. The environmental resources considered in the DEIS are biological
    [Show full text]
  • History of Radio Astronomy
    History of Radio Astronomy Reading for High School Students Getsemary Báez Introduction form of radiation involved (soon known as electro- Radio Astronomy, a field that has strongly magnetic waves). Nevertheless, it was Oliver Heavi- evolved since the end of World War II, has become side who in conjunction with Willard Gibbs in 1884 one of the most important tools of astronomical ob- modified the equations and put them into modern servations. Radio astronomy has been responsible for vector notation. a great part of our understanding of the universe, its A few years later, Heinrich Hertz (1857- formation, composition, interactions, and even pre- 1894) demonstrated the existence of electromagnetic dictions about its future path. This article intends to waves by constructing a device that had the ability to inform the public about the history of radio astron- transmit and receive electromagnetic waves of about omy, its evolution, connection with solar studies, and 5m wavelength. This was actually the first radio the contribution the STEREO/WAVES instrument on wave transmitter, which is what we call today an LC the STEREO spacecraft will have on the study of oscillator. Just like Maxwell’s theory predicted, the this field. waves were polarized. The radiation emissions were detected using a 1mm thin circle of copper wire. Pre-history of Radio Waves Now that there is evidence of electromag- It is almost impossible to depict the most im- netic waves, the physicist Max Planck (1858-1947) portant facts in the history of radio astronomy with- was responsible for a breakthrough in physics that out presenting a sneak peak where everything later developed into the quantum theory, which sug- started, the development and understanding of the gests that energy had to be emitted or absorbed in electromagnetic spectrum.
    [Show full text]
  • Radio Astronomy
    Edition of 2013 HANDBOOK ON RADIO ASTRONOMY International Telecommunication Union Sales and Marketing Division Place des Nations *38650* CH-1211 Geneva 20 Switzerland Fax: +41 22 730 5194 Printed in Switzerland Tel.: +41 22 730 6141 Geneva, 2013 E-mail: [email protected] ISBN: 978-92-61-14481-4 Edition of 2013 Web: www.itu.int/publications Photo credit: ATCA David Smyth HANDBOOK ON RADIO ASTRONOMY Radiocommunication Bureau Handbook on Radio Astronomy Third Edition EDITION OF 2013 RADIOCOMMUNICATION BUREAU Cover photo: Six identical 22-m antennas make up CSIRO's Australia Telescope Compact Array, an earth-rotation synthesis telescope located at the Paul Wild Observatory. Credit: David Smyth. ITU 2013 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. - iii - Introduction to the third edition by the Chairman of ITU-R Working Party 7D (Radio Astronomy) It is an honour and privilege to present the third edition of the Handbook – Radio Astronomy, and I do so with great pleasure. The Handbook is not intended as a source book on radio astronomy, but is concerned principally with those aspects of radio astronomy that are relevant to frequency coordination, that is, the management of radio spectrum usage in order to minimize interference between radiocommunication services. Radio astronomy does not involve the transmission of radiowaves in the frequency bands allocated for its operation, and cannot cause harmful interference to other services. On the other hand, the received cosmic signals are usually extremely weak, and transmissions of other services can interfere with such signals.
    [Show full text]
  • Wikipedia, the Free Encyclopedia
    SKA newsletter Volume 21 - April 2011 The Square Kilometre Array Exploring the Universe with the world’s largest radio telescope www.skatelescope.org Please click the relevant section title to skip to that section 03 Project news 04 From the SPDO 05 SKA science 08 Engineering update 10 Site characterisation 12 Outreach update 14 Industry participation 17 News from around the world 18 Africa 20 Australia and New Zealand 23 Canada 25 China 28 Europe 31 India 33 US 35 Future meetings and events Project news Project news 04 From the SPDO Crucial steps for the SKA project were At its first meeting on 2 April, the Founding taken in the last week of March 2011. A Board decided that the location of the SKA Founding Board was created with the Project Office (SPO) will be at the Jodrell aim of establishing a legal entity for the Bank Observatory near Manchester in the project by the time of the SKA Forum in UK. This decision followed a competitive Canada in early July, as well as agreeing bidding process in which a number of the resourcing of the Project Execution excellent proposals were evaluated in an Plan for the Pre-construction Phase international review process. The SPO, which from 2012 to 2015. The Founding Board is hoped to grow to 60 people over the next replaces the Agencies SKA Group with four years, will supersede the SPDO currently immediate effect. Prof John Womersley based at the University of Manchester. The from the UK’s Science and Technology physical move to a new building at Jodrell Facilities Council (STFC) was elected Bank Observatory is scheduled for mid-2012.
    [Show full text]
  • A Scalable Correlator Architecture Based on Modular FPGA Hardware, Reuseable Gateware, and Data Packetization
    A Scalable Correlator Architecture Based on Modular FPGA Hardware, Reuseable Gateware, and Data Packetization Aaron Parsons, Donald Backer, and Andrew Siemion Astronomy Department, University of California, Berkeley, CA [email protected] Henry Chen and Dan Werthimer Space Science Laboratory, University of California, Berkeley, CA Pierre Droz, Terry Filiba, Jason Manley1, Peter McMahon1, and Arash Parsa Berkeley Wireless Research Center, University of California, Berkeley, CA David MacMahon, Melvyn Wright Radio Astronomy Laboratory, University of California, Berkeley, CA ABSTRACT A new generation of radio telescopes is achieving unprecedented levels of sensitiv- ity and resolution, as well as increased agility and field-of-view, by employing high- performance digital signal processing hardware to phase and correlate large numbers of antennas. The computational demands of these imaging systems scale in proportion to BMN 2, where B is the signal bandwidth, M is the number of independent beams, and N is the number of antennas. The specifications of many new arrays lead to demands in excess of tens of PetaOps per second. To meet this challenge, we have developed a general purpose correlator architecture using standard 10-Gbit Ethernet switches to pass data between flexible hardware mod- ules containing Field Programmable Gate Array (FPGA) chips. These chips are pro- grammed using open-source signal processing libraries we have developed to be flexible, arXiv:0809.2266v3 [astro-ph] 17 Mar 2009 scalable, and chip-independent. This work reduces the time and cost of implement- ing a wide range of signal processing systems, with correlators foremost among them, and facilitates upgrading to new generations of processing technology.
    [Show full text]
  • Adventures in Radio Astronomy Instrumentation and Signal Processing
    Adventures in Radio Astronomy Instrumentation and Signal Processing by Peter Leonard McMahon Submitted to the Department of Electrical Engineering in partial fulfillment of the requirements for the degree of Master of Science in Electrical Engineering at the University of Cape Town July 2008 Supervisor: Professor Michael Inggs Co-supervisors: Dr Dan Werthimer, CASPER1, University of California, Berkeley Dr Alan Langman, Karoo Array Telescope arXiv:1109.0416v1 [astro-ph.IM] 2 Sep 2011 1Center for Astronomy Signal Processing and Electronics Research Abstract This thesis describes the design and implementation of several instruments for digi- tizing and processing analogue astronomical signals collected using radio telescopes. Modern radio telescopes have significant digital signal processing demands that are typically best met using custom processing engines implemented in Field Pro- grammable Gate Arrays. These demands essentially stem from the ever-larger ana- logue bandwidths that astronomers wish to observe, resulting in large data volumes that need to be processed in real time. We focused on the development of spectrometers for enabling improved pulsar2 sci- ence on the Allen Telescope Array, the Hartebeesthoek Radio Observatory telescope, the Nan¸cay Radio Telescope, and the Parkes Radio Telescope. We also present work that we conducted on the development of real-time pulsar timing instrumentation. All the work described in this thesis was carried out using generic astronomy pro- cessing tools and hardware developed by the Center for Astronomy Signal Processing and Electronics Research (CASPER) at the University of California, Berkeley. We successfully deployed to several telescopes instruments that were built solely with CASPER technology, which has helped to validate the approach to developing radio astronomy instruments that CASPER advocates.
    [Show full text]