Triplet stereo Radarsat-2/RCM HR images for DTM generation

Due to the specificity of space borne synthetic aperture radar (SAR) sensors, the stereoscopic pair can only be generated in across-track direction. However, the stereo can also be generated with triplet images when SAR system can span large values of incidence angle, such as Radarsat, TerraSAR and CosmoSky-Med. In this paper, the triplet stereo was introduced to high-resolution Radarsat-2 data for generating DTM. For this study, three high-resolution images from Radarsat-2 were acquired with 31°, 38° and 47° incidence angles over a rolling topography of north of Quebec City, Canada. Two main steps of generation of DTM, including the geometry for 3-D modeling and the radiometry for image matching were carried out. For 3-D modeling, one deterministic model, Tontin´s 3-D Radargrammetric Model, was applied to mono/stereo/triplet Radarsat-2 data. For image matching, a NCC algorithm was used. The differential GPS points and LiDAR products were used as reference data. Preliminaries results of triplet stereo with simulated SAR HR data of the new Canadian Radar Constellation Mission will be presented at IGARSSS 2012.