Abstract: | In this paper,the state of the art research on two pass DInSAR under the influence of reference DEM is summarized.This paper takes typical flat ground and mountain land at Qinghai Tibet Plateau as test regions.Using ERS Tandem image pairs without any deformation in theory and three external reference DEMs (SRTM,ASTER GDEM,1:50000 DEM),the two pass DInSAR processing with the help of ROI_PAC software is performed.In this paper,the way that multisource DEMs affects deformation results in two pass DInSAR has been proved.The fact is that SRTM is more suitable to be external reference DEM in two pass DInSAR.Finally,the differences of multisource DEMs data quality resulting in differences of registration errors between interferogram and DEM are explored,and the effect of data quality can be shown in final DInSAR phase errors. |