Range-recursive pre-Doppler STAP algorithm to reject range dependent clutter in airborne radar

This paper addresses the issue of employing pre-Doppler space time adaptive processing (STAP) in non side looking airborne radar. In this configuration, where the platform velocity is misaligned with the radar antenna axis, the clutter possesses specific properties : the space-time repartition of its spectral power depends on the range what induces difficulties to reject it. The range recursive STAP algorithms have already exhibited high performance to track this non stationarity in fully adaptive STAP. We here propose the use of these algorithms in a pre-Doppler architecture. This paper presents significant performance improvements offered by this element space approach compared with a fully architecture. A comparison with SMI and DBU methods associated with a pre-Doppler approach is also studied. We show that the proposed algorithm outperforms them in terms of SINR loss and computational cost.