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Elevation Modeling using Radargrammetry: Case study from Malaysia

This paper presents the generation of DEM using six pairs of Radarsat-1 images for part of tropical terrain in Malaysia. The images were acquired with various beam modes and incident angles and used to generate DEMs by means of radargrammetry based on two SAR imaging models: Range-Doppler and Co-linearity condition equations model. First, the physical basis of these two models was assessed, and then, the characters and the performance of these models were evaluated. For the latter the accuracies of the DEMs were assessed using reference data such as digital contour maps. The results of the analysis shows that for all stereo pairs, the accuracy of DEMs by the Range-Doppler model are better than the Co-linearity condition equation model. Finally, the relationship between the DEM accuracy and some important factors, such as orbit, beam mode, spatial resolution, the intersection angle and the impact of terrain, were analyzed.