A Motion Compensation Technique Based on GPS and Refined MapDrift For Ultr-wide Band SAR
Traditional motion compensation for airborne synthetic aperture radar (SAR) based on hardware requires motion-measurement and navigation system with high-accuracy, which is expensive. Based on the character that attitude information of aircraft is unnecessary for ultra-wide band SAR (UWB-SAR), a new motion compensation method combining real-time global position system (GPS) and our refined MapDrift (RMD) is proposed in this paper. The GPS information is used to correct most errors of aircraft, that is to say, the GPS position data are used to correct range delay of SAR echoes, and the GPS velocity data are used to correct most of phase error. After coarse compensation according to GPS, the residual phase errors are corrected by our RMD. The new method is verified by real UWB-SAR data and is very attractive for UWB-SAR for its cheapness