Calibration method for ATI errors based on signal subspace processing

A main problem of airborne synthetic aperture radar/ground moving target indicator(SAR/GMTI) based on the along track interferometry(ATI) technique is that varieties of error invalidate ATI and limit its application. The interferometric phase error which causes the performance decline in ATI ground moving target detection due to synchronization error and platform attitude error is analyzed and is investigated with detailed deduction. Signal subspace processing based on 2-D adaptive filtering is introduced to calibrate these errors and the moving target detection is achieved. The simulation results indicate that the scheme can reduce the sensitivity of ATI to errors and improves the performance of moving target detection.