SARDINIA APERTURE ARRAY DEMONSTRATOR: ELECTROMAGNETIC ANALYSIS AND MEASUREMENTS

The Sardinia Aperture Array Demonstrator (SAD) is an Italian project aimed at developing new technology in the area of Low-Frequency Aperture Arrays (LFAAs). The final objective of SAD is to test technologies and demonstrate concepts for a possible application in the LFAA instrument of the Square Kilometre Array (SKA). In LFAA, the electronically steered beam produced by a large number of antenna elements makes the digital signal processing extremely challenging. In this framework, the electromagnetic aspects of these large arrays are significant and an accurate analysis is mandatory. For instance in SAD, a lot of efforts have been addressed to design the antenna, to analyse its electromagnetic performance, to measure the antenna patterns by using an aerial artificial probe, to analyse the array behaviour and to set up an automatic procedure for monitoring the radio spectrum at the site. All these aspects are discussed in this article.