Extension of range migration algorithm for airborne spotlight SAR with velocity variation

To obtain the SAR images with high quality and the fast processing time in the airborne spotlight SAR with velocity variation, we propose a modified range migration algorithm (RAM) with resampling based on the extended Taylor approximation and the fast interpolation process. First, at the mixing stage of the reference signal and the raw data, we resample the azimuth position. Then, at the Stolt interpolation stage, we modify the original interpolation method. Finally, we test the effectiveness of the proposed method using a pulsed spotlight SAR simulator.