Aperture Array Configurations for SKA1 Core

Abstract: This memo considers some aspects of the configuration of the SKA1 Low Frequency Aperture Array, both at the element and station level. At the element level I propose a possible scenario for forming station beams where elements are shared between stations and apodisation is implemented, with the aim of improving filling factor, overall sensitivity and sidelobe performance; the disadvantages of such a scheme with regards to beam former requirements and shortest available baseline are also discussed. At the station level, a randomised configuration within a filled central region together with spiral arms is explored.