A signal processing architecture for space-based GMTI radar

Abstract

Ground moving target indicator (GMTI) radars detect and classify targets with low velocities. Placing such radars in the Earth's orbit can provide wide area coverage with high revisit rates. However, because of the radar's large footprint (on the ground) and high velocity, target signals must compete with extremely intense nearby clutter. Requirements on antenna aperture, bandwidth, coverage rate, and computational complexity all play significant roles in shaping the radar's signal processing chain. This paper describes a signal processing architecture that rejects interference. By addressing issues such as aperture configuration, bandwidth-induced decorrelation, adaptive training, and degree-of-freedom requirements, a multistage space-time adaptive processing (STAP) architecture is constructed.