Intrinsic advantages of the w component and spherical imaging for wide-field radio interferometry

TL;DR

This paper reviews how the w component and spherical imaging enhance wide-field radio interferometric imaging, improving image quality through increased incoherence and reduced sparsity in spherical space.

Contribution

It highlights the benefits of using the w component and spherical coordinate recovery in compressed sensing for wide-field radio interferometry, emphasizing improved image reconstruction.

Findings

Enhanced spread spectrum phenomenon due to w component

Reduced sparsity by recovering images on the sphere

Improved image quality in wide-field interferometry

Abstract

Incorporating wide-field considerations in interferometric imaging is of increasing importance for next-generation radio telescopes. Compressed sensing techniques for interferometric imaging have been extended to wide fields recently, recovering images in the spherical coordinate space in which they naturally live. We review these techniques, highlighting: (i) how the effectiveness of the spread spectrum phenomenon, due to the w component inducing an increase of measurement incoherence, is enhanced when going to wide fields; and (ii) how sparsity is reduced by recovering images directly on the sphere. Both of these properties act to improve the quality of reconstructed images.