Interpolation-free Coregistration and Phase-Correction of Airborne SAR Interferograms

摘要

This letter discusses the detection and correction of\udresidual motion errors that appear in airborne synthetic aperture\udradar (SAR) interferograms due to the lack of precision in the navigation\udsystem. As it is shown, the effect of this lack of precision is\udtwofold: azimuth registration errors and phase azimuth undulations.\udUp to now, the correction of the former was carried out by\udestimating the registration error and interpolating, while the latter\udwas based on the estimation of the phase azimuth undulations to\udcompensate the phase of the computed interferogram. In this letter,\uda new correction method is proposed, which avoids the interpolation\udstep and corrects at the same time the azimuth phase undulations.\udAdditionally, the spectral diversity technique, used to estimate\udregistration errors, is critically analyzed. Airborne L-band\udrepeat-pass interferometric data of the German Aerospace Center\ud(DLR) experimental airborne SAR is used to validate the method