PHASED ARRAY FEED CALIBRATION, BEAMFORMING, AND IMAGING

Phased array feeds (PAFs) for reflector antennas offer the potential for increased reflector field of view and faster survey speeds. To address some of the development challenges that remain for scientifically useful PAFs, including calibration and beamforming algorithms, sensitivity optimization, and demonstration of wide field of view imaging, we report experimental results from a 19 element room temperature L-band PAF mounted on the Green Bank 20 Meter Telescope. Formed beams achieved an aperture efficiency of 69% and a system noise temperature of 66 K. Radio camera images of several sky regions are presented. We investigate the noise performance and sensitivity of the system as a function of elevation angle with statistically optimal beamforming and demonstrate cancelation of radio frequency interference sources with adaptive spatial filtering.

[1]  M. Jensen,et al.  Effects of mutual coupling on interference mitigation with a focal plane array , 2005, IEEE Transactions on Antennas and Propagation.

[2]  R. Giovanelli,et al.  H I clouds in the proximity of M 33 , 2008, 0806.0412.

[3]  B. Jeffs,et al.  Gain and Aperture Efficiency for a Reflector Antenna With an Array Feed , 2006, IEEE Antennas and Wireless Propagation Letters.

[4]  Albert-Jan Boonstra,et al.  The effect of blanking of TDMA interference on radio-astronomical observations: experimental results , 2000, 2000 IEEE International Conference on Acoustics, Speech, and Signal Processing. Proceedings (Cat. No.00CH37100).

[5]  Karl F. Warnick,et al.  Signal Processing for Phased Array Feeds in Radio Astronomical Telescopes , 2008, IEEE Journal of Selected Topics in Signal Processing.

[6]  R. B. Barreiro,et al.  Component separation methods for the PLANCK mission , 2008, 0805.0269.

[7]  Stephen G. Wilson,et al.  COMBATING PULSED RADAR INTERFERENCE IN RADIO ASTRONOMY , 2003 .

[8]  Amir Leshem,et al.  MULTICHANNEL INTERFERENCE MITIGATION TECHNIQUES IN RADIO ASTRONOMY , 2000, astro-ph/0005359.

[9]  M. Putman.  Potential Condensed Fuel for the Milky Way , 2006, astro-ph/0603650.

[10]  T. Dame,et al.  A New Spiral Arm of the Galaxy: The Far 3 kpc Arm , 2008, 0807.1752.

[11]  The WSRT wide-field H I survey - II. Local Group features , 2003, astro-ph/0312323.

[12]  J. Richard Fisher,et al.  Bayesian detection of radar interference in radio astronomy , 2006 .

[13]  Glen I. Langston,et al.  The Smith Cloud: A High-Velocity Cloud Colliding with the Milky Way , 2008, 0804.4155.

[14]  Kamal Sarabandi,et al.  Antennas and Propagation , 2019, 2019 14th International Conference on Advanced Technologies, Systems and Services in Telecommunications (TELSIKS).

[15]  J. Black,et al.  Models of interstellar clouds. I. The Zeta Ophiuchi cloud , 1977 .

[16]  Peter G. Martin,et al.  The Canadian Galactic Plane Survey , 1998, Publications of the Astronomical Society of Australia.

[17]  B.D. Van Veen,et al.  Beamforming: a versatile approach to spatial filtering , 1988, IEEE ASSP Magazine.

[18]  W. L. Combrinck,et al.  CO-EXISTING WITH GLONASS: OBSERVING THE 1612 MHZ HYDROXYL LINE , 1994 .

[19]  Felix J. Lockman,et al.  On the Continuing Formation of the Andromeda Galaxy: Detection of H I Clouds in the M31 Halo , 2003, astro-ph/0311571.

[20]  Steven W. Ellingson,et al.  Mitigation of Radar Interference in L-Band Radio Astronomy , 2003 .

[21]  J. R. Fisher,et al.  Mitigation of Pulsed Interference to Redshifted H I and OH Observations between 960 and 1215 Megahertz , 2005 .

[22]  Stephen G. Wilson,et al.  Excision of Distance Measuring Equipment Interference from Radio Astronomy Signals , 2005 .

[23]  G. Lazzi.  Antennas and Wireless Propagation Letters , 2008 .

[24]  Karl F. Warnick,et al.  Bias Corrected PSD Estimation for an Adaptive Array With Moving Interference , 2008, IEEE Transactions on Signal Processing.

[25]  H. V. Trees.  Detection, Estimation, And Modulation Theory , 2001 .

[26]  M. V. Ivashina,et al.  Apertif, a focal plane array for the WSRT , 2008, 0806.0234.

[27]  Brian D. Jeffs,et al.  Radar interference blanking in radio astronomy using a Kalman tracker , 2005 .

[28]  Molecular Hydrogen in Infrared Cirrus , 2005, astro-ph/0507587.

[29]  P. Russer,et al.  Minimizing the Noise Penalty Due to Mutual Coupling for a Receiving Array , 2009, IEEE Transactions on Antennas and Propagation.

[30]  K.F. Warnick,et al.  Optimal Noise Matching for Mutually Coupled Arrays , 2007, IEEE Transactions on Antennas and Propagation.

[31]  B. Jeffs,et al.  Efficiencies and System Temperature for a Beamforming Array , 2008, IEEE Antennas and Wireless Propagation Letters.

[32]  B. Jeffs,et al.  Experimental verification of radio frequency interference mitigation with a focal plane array feed , 2007 .

[33]  S. Ellingson,et al.  Removal of the GLONASS C/A Signal from OH Spectral Line Observations Using a Parametric Modeling Technique , 2001 .

[34]  Harry L. Van Trees,et al.  Detection, Estimation, and Modulation Theory, Part I , 1968 .

[35]  Karl F. Warnick,et al.  Programmable Real-Time Cancellation of GLONASS Interference with the Green Bank Telescope , 2005 .

[36]  M.V. Ivashina,et al.  Equivalent System Representation to Model the Beam Sensitivity of Receiving Antenna Arrays , 2008, IEEE Antennas and Wireless Propagation Letters.

[37]  Dennis Roddy,et al.  Satellite Communications , 1989 .