Detecting moving targets in SAR imagery through shadow tracking

Abstract:
In this paper a novel technique is presented for detecting moving targets in SAR imagery by tracking the shadow of the target over multiple looks instead of using the target direct energy return. Unlike the SAR image of a moving target that is blurred and displaced, the shadow of the target is displayed at the true target location. The detection performance using shadow is primarily independent of the target radar cross-section and depends upon the clutter to noise signal level. The potential moving targets are detected by applying change detection to a series of multi-temporal SAR images. This provides excellent discrimination between shadows of moving targets from static target shadows and thereby maintains a low false alarm rate. The technique is demonstrated successfully using real radar data obtained from a short range spotlight SAR system.