The digital signal processing platform for the low frequency aperture array : preliminary results on the data acquisition unit

Abstract

A signal processing hardware platform has been developed for the Low Frequency Aperture Array component of the Square Kilometre Array. The processing board, called an Analog Digital Unit (ADU), is able to acquire and digitize broadband (up to 500MHz bandwidth) radio-frequency streams from 16 dual polarized antennas, channel the data streams and then combine them flexibly as part of a larger beamforming system. It is envisaged that there will be more than eight thousand of these signal processing platforms in the first phase of the Square Kilometre Array, so particular attention has been devoted to ensuring the design is low-cost and low-power. This paper describes the main features of the data acquisition unit of such a platform and presents preliminary results characterising its performance.