Development of a Phased-Array feed Demonstrator for radio telescopes

Abstract

Future centimetre-wavelength radio telescopes will use low-noise phased arrays as feed antennas. Two key reasons for developing this technology is that it enables the radio telescope to have several simultaneous beams on the sky, increasing the speed of the instrument, and because it allows the properties of the feed to be optimised. However, to date only two experimental demonstrations of phased-array feeds on radio telescopes have been performed. We are in the planning stages of an array that will thoroughly demonstrate the capabilities of this technology. This engineering demonstrator will consist of an array of Vivaldi antennas feeding low-noise amplifiers. After amplification the signal will be down-converted and digitized. This data will be stored for off-line beamforming on desktop computers. From these data sets we will be able to demonstrate not only rudimentary beamforming, but also more sophisticated operations such as optimisation of the feed pattern and interference cancellation. Current plans and progress of this project will be reviewed.