The square kilometer array (SKA) antenna

One of the major approaches to satisfying future goals for radio astronomy is a wide bandwidth receiving array that forms a radio telescope with one square kilometer of collecting area. The array will operate over a decade of frequency, approximately 200 MHz to 2000 MHz, it will provide polarimetric information for at least 100 simultaneous beams, and it will form interferometric images with 0.1 arcsec angular resolution at 1.4 GHz. Such an array will be comprised of approximately 10/sup 8/ wide bandwidth elements and will require calibration, digital beamforming, and adaptive nulling. This paper describes the radiating aperture design that is currently employed for the demonstration system. It is likely that the final array design will resemble this demonstration aperture, which utilizes wide bandwidth Vivaldi tapered slot antennas for the individual elements. Design information and results for prototypes and the demonstrator are presented.