Global space-based ground surveillance: Mission utility and performance of Discoverer II

The Discoverer II (DII) program will demonstrate an affordable space-based radar (SBR) with High Range Resolution Ground Moving Target Indication (HRR-GMTI), Synthetic Aperture Radar (SAR) imaging, and Digital Terrain Elevation Data (DTED) collection that is expected to revolutionize reconnaissance, surveillance and precision targeting support to the tactical warfighter. This paper presents a utility analysis of DII, including mobile missile launcher surveillance, strategic facilities monitoring, maritime surveillance, and detection of underground facility construction. A subbanding approach to the signal processing that allows parallel implementation is presented. A 30 Gflop chip set capable of wideband channelization and delivering 128 point FFTs every 200 nsec, with 25 to 50 GOPS per Watt power efficiency is described. Performance analyses of space time adaptive processing (STAP), GMTI tracker operation, STAP clutter suppression and GMTI tracking results from airborne collections are presented. Approaches for collecting precision DTED, and airborne testbed results near the DTED 5 level are presented.