Calibration schemes with O(N log N) scaling for large-N radio interferometers built on a regular grid

@article{Gorthi2020CalibrationSW,
title={Calibration schemes with O(N log N) scaling for large-N radio interferometers built on a regular grid},
author={Deepthi Gorthi and Aaron Parsons and Joshua S. Dillon},
journal={Monthly Notices of the Royal Astronomical Society},
year={2020},
volume={500},
pages={66-81}
}
• Published 6 May 2020
• Computer Science
• Monthly Notices of the Royal Astronomical Society
Future generations of radio interferometers targeting the 21\,cm with $N\gg 1000$ antennas could face a significant computational challenge in building correlators with the traditional architecture, whose computational resource requirement scales as $\mathcal{O}(N^2)$ with array size. The fundamental output of such correlators are the cross-correlation products of all antenna pairs in the array. The FFT-correlator architecture reduces the computational resources scaling to $\mathcal{O}(N\log_2N… 1 Citations Figures from this paper Redundant-baseline calibration of the hydrogen epoch of reionization array • Physics Monthly Notices of the Royal Astronomical Society • 2020 In 21-cm cosmology, precision calibration is key to the separation of the neutral hydrogen signal from very bright but spectrally smooth astrophysical foregrounds. The Hydrogen Epoch of Reionization References SHOWING 1-10 OF 39 REFERENCES An efficient feedback calibration algorithm for direct imaging radio telescopes • Physics • 2017 We present the E-field Parallel Imaging Calibration (EPICal) algorithm, which addresses the need for a fast calibration method for direct imaging radio astronomy correlators. Direct imaging involves A real-time, all-sky, high time resolution, direct imager for the long wavelength array • Computer Science Monthly Notices of the Royal Astronomical Society • 2019 The first successful deployment of the E-field Parallel Imaging Correlator (EPIC) on the LWA station in Sevilleta, New Mexico, USA (LWA-SV) is described and the imaging performance is verified by detecting a meteor impact on the atmosphere using continuous all-sky imaging at 50 ms time resolution. A generic and efficient E-field Parallel Imaging Correlator for next-generation radio telescopes • Physics • 2015 Modern radio telescopes are favouring densely packed array layouts with large numbers of antennas ($N_\textrm{a}\gtrsim 1000\$). Since the complexity of traditional correlators scales as
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