Multi-Look Stripmap SAR Processing Algorithm with Built-In Correction of Geometric Distortions

SAR systems installed on small aircrafts suffer from trajectory deviations and instabilities of antenna orientation. These kinds of motion errors lead to significant geometric distortions in SAR images. In the paper, we describe a time-domain multi-look stripmap SAR processing algorithm with built-in correction of geometric distortions. In the algorithm, the azimuth reference functions and range migration curves are specially designed to produce SAR images directly on a correct rectangular grid on the ground plane. The proposed technique has been successfully tested by using a Ku-band airborne SAR system.