Study on accurate estimation of baseline parameters of space-borne InSAR based on GCPs

The estimation of baseline parameters is an important step in SAR interferometry (InSAR) processing and applications, because its accuracy influences directly the quality of the final DEM generated from interferogram. In this paper, some classical methods of baseline parameters estimation, based respectively on precise orbit data, interferogram and Ground Control Points(GCPs), are summarized and compared. For it is recognized that the baseline parameters estimation based on GCPs is the most reliable method at present, this paper concentrate on researching optimizing model of several correction algorithms based on GCPs for baseline parameters. The approach is tested with ENVISAT ASAR data over the Dujiangyan region of Sichuan Province of China. Finally, the feasibility and rationality of the proposed method is showed by comparing the quality of DEM generated from interferogram with SRTM DEM.