A space-fed phase array for surveillance from space

A novel space-fed radar antenna called a venetian blind is proposed for all-weather wide area surveillance from space. The antenna can support both tasked and untasked operation. In its untasked form (essentially a space-fed passive lens), it achieves off-axis squint angles of many beamwidths with negligible performance degradation. It is inherently insensitive to mechanical distortion, and is a first step in the evolution to the more complex tasked system antenna. The antenna lens consists of easily manufactured slats with microstrip dipole radiating elements and matching networks on a dielectric substrate. Phase control is achieved with low-loss delay lines in the passive lens or active transmit/receive modules if electronic scan is desired