Two-Step Detector for RADARSAT-2's Experimental GMTI Mode

Ground moving target indication (GMTI) from space has currently raised interest from wide area traffic monitoring as well as for military surveillance activities. This paper presents theoretical and real data GMTI results of RADARSAT-2's Moving Object Detection Experiment based on data gathered during the commissioning phase in February 2008. The proposed constant false alarm rate target detection is based on a novel and thorough analysis of the multilook test statistics. The practical and relevant case in which a target, for instance a passenger car, occurs in only
l
-out-of-
n
ground resolution multilook cells is analyzed. This general case is analyzed for the determination of adequate detection thresholds as well as the anticipated probability of detection
P
_d
particularly with regard to a varying degree of terrain heterogeneity and target characteristics. The overall false alarm rate
P
_fa
is significantly reduced by a complementary detection step using the along-track interferometric phase. The validity of these theoretical findings are corroborated by real two-channel space-based synthetic aperture radar-GMTI data of civilian vehicles of opportunity, whose main parameters have been estimated and compared with the derived Cramér-Rao Bounds.