Phased-array antenna system development for radio-astronomy applications [Antenna Applications Corner]

Phased-array antenna systems are playing an increasingly significant role in passive, i.e., receive-only, radio-astronomy applications. They provide attractive features, such as a large instantaneous field-of-view, multi-beaming capability, and rapid response time. In this paper, we present an overview of current developments in phased-array antenna systems for radio astronomy, with an emphasis on the design challenges posed by this application.