An enhanced approach based on energy loss for multichannel SAR-GMTI systems in heterogeneous environment

For ground moving target indication (GMTI) in heterogeneous terrains, most detectors could not effectively solve the problem of a high probability of false alarms (PFA) due to the presence of isolated interference with large radar cross section (RCS). To address this issue, we construct a new criterion called as energy loss, which is the energy difference between input and output in the adaptive processing, and develop an enhanced approach based on energy loss for multichannel synthetic aperture radar (SAR)-GMTI systems in heterogeneous environment. In this method, the magnitude-based detection after clutter suppression is first applied to detect potential targets with a relatively low threshold. Then, a complementary detection based on energy loss test is performed to reduce false alarms. To compute the detection thresholds, the statistics of the energy loss test and the overall PFA of the detection approach are analyzed theoretically. Finally, the experimental results on simulations and real data, collected in China's urban area, demonstrate the superiority of the proposed approach compared with state-of-art methods.