Effects of manoeuvre on space time adaptive processing performance

Space time adaptive processing (STAP) has been actively considered for look down airborne radar where target signals have to compete with strong ground clutter returns. It is now well known that in SLAR (sideways looking airborne radar) a simple linear relationship between clutter Doppler and spatial frequency can be exploited to achieve clutter rejection via two dimensional filtering in the spatial and temporal frequency domains. The two dimensional filtering can be realised via the sampling of a coherent pulse train with a phased array antenna. Non-adaptive filter weight solutions, which theoretically achieve full clutter suppression, correspond to the well known DPCA (displaced phase centre antenna) technique. In STAP, the two dimensional filter weights are calculated adaptively, leading to the advantages over DPCA of robustness to errors and a capability for simultaneous suppression of jamming and clutter.