An improved DEM refinement approach for DEM reconstruction with high resolution InSAR data in mountainous area

An improved DEM refinement approach is presented in this paper to produce Digital Elevation Model (DEM) of 1:50,000 in mountainous areas with steep slope using high resolution SAR data. In order to deduce the precise DEM, a coarse external DEM is utilized to reduce the impact of phase errors on the InSAR-generated DEM. The proposed algorithm should include two parts: the first step is to model and remove phase trends with a linear regression analysis before converting phase to height. The second step is to filter unreliable height points before interpolating DEM product from InSAR height map. The preliminary experimental results show that our approach improved the accuracy of the resulting DEM significantly without any ground control points, the DEM reconstruction experiment derived from the TerraSAR data has been proved fulfill the 1:50,000 DEM in mountainous areas.