Reconstruction of InSAR DEM Using ERS-1/2 Interferogram and SRTM Data*

摘要

Though the Interferometric Synthetic Aperture Radar (InSAR) processing can produce Digital Elevation Model (DEM), the accuracy of the InSAR derived DEM need to be improved because of the impact of phase errors. To solve this problem, we propose a new approach which includes three steps. Firstly we estimate the baseline and utilize precise orbit data to obtain higher co-registration accuracy. Then we model and remove phase trends via linear regression analysis before converting phase to height with critical points selected in high coherence regions. Finally the interferometric phase in low coherence regions is stimulated with the use of SRTM DEM. One pair of ERS-1/2 images and SRTM data covering the mountainous region in central China is utilized in this work. The experiment shows the effectiveness of our approach.