Target detection in post-STAP undernulled clutter

We describe a new detection algorithm for use with adaptively beamformed radar data. It is designed to take advantage of the a priori knowledge of the location of the ground clutter azimuth-Doppler ridge. In real data, the clutter is likely to be non-homogeneous, leading to the possibility of undernulled clutter discretes appearing in the adaptive beamformer output, the magnitude and frequency of which depend directly on the choice of training set for the adaptive nulling algorithm. The new detection algorithm estimates the magnitude of such undernulled clutter, and adjusts its threshold to account for the amount of residual clutter appearing in the adaptive beam. The advantage of such a detector lies in reducing the number of false alarms due to clutter discretes while maintaining detector sensitivity in areas in which the clutter discretes are well-nulled by the adaptive nulling algorithm.