Stop-and-go approximation effects on COSMO-SkyMed spotlight SAR data

Spotlight SAR data processing is already an established topic; efficient and accurate solutions have been proposed over the last years. However, the assumptions of these algorithms start to be invalid when applied to high-resolution spotlight SAR data. In particular the motion of the satellite during the transmission and reception of the chirp signal deteriorate the impulse response function (IRF), if not properly considered (so called stop-and-go approximation). In this paper stop-and-go approximation effects on COSMO-SkyMed (CSK) civilian spotlight SAR data are showed, demonstrating that it plays a not negligible role on SAR images with a resolution in the meter regime. A new data processing chain including stop-and-go correction is proposed, for high precision image formation of CSK civilian spotlight SAR data. The proposed approach is validated using real data acquired by CSK satellites in the civilian spotlight mode.