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}
}
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… 
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