Performance Analysis on Clutter Suppression of Polarization Space Time Adaptive Processing for Airborne Radar

It is known that polarization space time adaptive processing (PSTAP) can improve the ability of clutter suppression and low speed target detection for airborne radar. In this paper, we analyze the influencing factors of PSTAP output signal to clutter plus noise ratio (SCNR), based on the clutter model with resolution grid. Analytical expression of SCNR is deduced, which reveals the mechanism that three key elements, e.g. the polarization angle between target and clutter, the polarization correlation coefficient of clutter and the clutter polarization power ratio, effect the performance of PSTAP. It is further proved that the output SCNR of PSTAP is directly proportional to the polarization correlation coefficient of clutter and inversely proportional to the clutter power ratio, when the polarization angle between target and clutter is large. Furthermore, experimental data show that output SCNR of PSTAP is superior to that of STAP, especially in low-speed target detection, which is consistent with theoretical analysis. This paper provides helpful insights and paves the way for PSTAP application in airborne radar.