Full-wave analysis of mutual coupling in the HIRAX radio telescope

The Hydrogen Intensity and Real-time Analysis experiment (HIRAX [1]) isa radio telescope which will consist of 1000 6m-wide, closely-packed and orientable dishes operating between 400 and 800 MHz. The experiment aims to indirectly constrain the properties of cosmological quantities, such as Dark Energy, by measuring the hydrogen intensity delay power spectrum and extracting the Baryon Acoustic Oscillations (BAO) feature. The principle is to separate between the cosmological (BAO) information residing at high delay k
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-modes and the foreground signal residing at low delays. However, as is the case for other similar telescopes [2], mutual coupling between neighboring, but also far-apart, antennas can cause the foreground signal to contaminate high delay modes thereby reducing the detection window of the cosmological signal.