Algorithms for FFT Beamforming Radio Interferometers
Radio interferometers consisting of identical antennas arranged on a regular lattice permit fast Fourier transform beamforming, which reduces the correlation cost fromω (n2) in the number of antennas toω(n log n). We develop a formalism for describing this process and apply this formalism to derive...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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American Astronomical Society
2021
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| Online Access: | https://hdl.handle.net/1721.1/129686 |
| _version_ | 1826210336409124864 |
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| author | Masui, Kiyoshi Shaw, J Richard Ng, Cherry Smith, Kendrick M Vanderlinde, Keith Paradise, Adiv |
| author2 | MIT Kavli Institute for Astrophysics and Space Research |
| author_facet | MIT Kavli Institute for Astrophysics and Space Research Masui, Kiyoshi Shaw, J Richard Ng, Cherry Smith, Kendrick M Vanderlinde, Keith Paradise, Adiv |
| author_sort | Masui, Kiyoshi |
| collection | MIT |
| description | Radio interferometers consisting of identical antennas arranged on a regular lattice permit fast Fourier transform beamforming, which reduces the correlation cost fromω (n2) in the number of antennas toω(n log n). We develop a formalism for describing this process and apply this formalism to derive a number of algorithms with a range of observational applications. These include algorithms for forming arbitrarily pointed tied-array beams from the regularly spaced Fourier transform-formed beams, sculpting the beams to suppress sidelobes while only losing percent-level sensitivity, and optimally estimating the position of a detected source from its observed brightness in the set of beams. We also discuss the effect that correlations in the visibility-space noise, due to cross talk and sky contributions, have on the optimality of Fourier transform beamforming, showing that it does not strictly preserve the sky information of the n2 correlation, even for an idealized array. Our results have applications to a number of upcoming interferometers, in particular the Canadian Hydrogen Intensity Mapping Experiment-Fast Radio Burst (CHIME/FRB) project. ©2019. The American Astronomical Society. All rights reserved. |
| first_indexed | 2024-09-23T14:48:10Z |
| format | Article |
| id | mit-1721.1/129686 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T14:48:10Z |
| publishDate | 2021 |
| publisher | American Astronomical Society |
| record_format | dspace |
| spelling | mit-1721.1/1296862022-10-01T22:34:43Z Algorithms for FFT Beamforming Radio Interferometers Masui, Kiyoshi Shaw, J Richard Ng, Cherry Smith, Kendrick M Vanderlinde, Keith Paradise, Adiv MIT Kavli Institute for Astrophysics and Space Research Massachusetts Institute of Technology. Department of Physics Radio interferometers consisting of identical antennas arranged on a regular lattice permit fast Fourier transform beamforming, which reduces the correlation cost fromω (n2) in the number of antennas toω(n log n). We develop a formalism for describing this process and apply this formalism to derive a number of algorithms with a range of observational applications. These include algorithms for forming arbitrarily pointed tied-array beams from the regularly spaced Fourier transform-formed beams, sculpting the beams to suppress sidelobes while only losing percent-level sensitivity, and optimally estimating the position of a detected source from its observed brightness in the set of beams. We also discuss the effect that correlations in the visibility-space noise, due to cross talk and sky contributions, have on the optimality of Fourier transform beamforming, showing that it does not strictly preserve the sky information of the n2 correlation, even for an idealized array. Our results have applications to a number of upcoming interferometers, in particular the Canadian Hydrogen Intensity Mapping Experiment-Fast Radio Burst (CHIME/FRB) project. ©2019. The American Astronomical Society. All rights reserved. 2021-02-05T18:11:37Z 2021-02-05T18:11:37Z 2019-06 2019-05 2020-11-03T14:59:23Z Article http://purl.org/eprint/type/JournalArticle 1538-4357 https://hdl.handle.net/1721.1/129686 Masui, Kiyoshi W. et al., "Algorithms for FFT Beamforming Radio Interferometers." Astrophysical Journal 879, 1 (July 2019): 16 ©2019 Authors en https://dx.doi.org/10.3847/1538-4357/AB229E Astrophysical Journal Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Astronomical Society The American Astronomical Society |
| spellingShingle | Masui, Kiyoshi Shaw, J Richard Ng, Cherry Smith, Kendrick M Vanderlinde, Keith Paradise, Adiv Algorithms for FFT Beamforming Radio Interferometers |
| title | Algorithms for FFT Beamforming Radio Interferometers |
| title_full | Algorithms for FFT Beamforming Radio Interferometers |
| title_fullStr | Algorithms for FFT Beamforming Radio Interferometers |
| title_full_unstemmed | Algorithms for FFT Beamforming Radio Interferometers |
| title_short | Algorithms for FFT Beamforming Radio Interferometers |
| title_sort | algorithms for fft beamforming radio interferometers |
| url | https://hdl.handle.net/1721.1/129686 |
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