Bistatic surveillance concept of operations

Space-based radars are being considered for civilian and military surveillance of ground and air moving vehicles because of their worldwide field of regard, and their inherent potential for surveillance of locations denied to other radars for political or geographical reasons. Monostatic radars will provide detection and tracking of moving objects, but are limited by affordable aperture sizes to large target cross sections or infrequent revisit rates. Several authors have postulated that bistatic operation between a space-based illuminator and airborne receiver is one effective method of improving on these limitations. However, the ability to fully utilize the area coverage rate of the bistatic hybrid space-based radar is limited by a small receiver footprint as compared to the spaceborne transmitter. This paper develops the bistatic area coverage radar range equation, as compared to the monostatic equivalent. A description of multibeam receiver operation is presented along with the radar signal processing to provide the necessary signal-to-noise ratio for target detection. Finally, a first-order consideration of the waveform design approach to enable bistatic STAP processing for target detection is presented.