Passive SAR Using Small Satellite Receivers for Persistent Earth Observation

This paper proposes a potential solution for near-persistent Earth observation applications. The concept is of a passive Synthetic Aperture Radar system, where the transmitter is a digital television broadcasting station and the receivers are on board micro-/nano-satellites in low earth orbit. The essential reduction in satellite costs allows a constellation of radar satellites to be launched, enabling potentially persistent monitoring anywhere on Earth. As the preliminary proof of concept, the fundamental properties of the system, i.e. power budget and spatial resolution, are investigated.