Along-Track Motion Compensation for Strip-Map SAR Based on Resampling

The airborne or vehicle-based SARs are very vulnerable to the influences of airflows or road conditions so as to deviate from the predicted trajectory, which undermines the uniformity of the azimuth sampling. As a result, the SAR image quality can get impaired in varying degrees. Since the SAR systems are sensible to the track deviation, the motion compensation (MOCO) algorithms are always applied as pre-processing of SAR raw data. In this paper, mainly with regard to the motion error caused by the forward velocity variation, a 'resampling MOCO' algorithm is proposed as an auxiliary of the widely used bulk MOCO. The simulation result has verified that the performance of the fundamental bulk MOCO algorithm is greatly improved utilizing the proposed method.