RRI Efficient Linear-array Imager: salient aspects

Abstract

Recently, a new optics entitled Efficient Linear-array Imager [1] has been proposed to use radio receivers efficiently for imaging the skies. The new optics demonstrates that it is possible to trade instantaneous sensitivity to instantaneous field-of-view while conserving the AΩ product. For a dish of size D fitted with N receivers, this product is ~D 2 N. This can be rewritten as 2 (D × D/N/2) × (N/2) 2 . The first part, 2 (D × D/N/2), implies two orthogonal areas of elliptical cross section with an N/2 aspect ratio. The second part, (N/2) 2 , indicates the number of simultaneous beams formed with N receivers. Thus, the resultant configuration is two telescopes of elliptical cross sections laid in a cross-configuration, each fitted with N/2 receivers. Then, by cross correlating each set of receivers with the orthogonal set of receivers, one obtains the (N/2) 2 beams.