Relief restitution by radargrammetry using RADARSAT images: example in French West Indies

Relief restitution by radargrammetry is definitively operational using aircraft SAR images, nevertheless the use of satellite SAR images to obtain DEM by this method was not fully satisfactory up to now. This is due to the satellite features which were not dedicated to provide stereoscopic capabilities. With the launch of RADARSAT, radargrammetry using satellite SAR images will be more efficient and operational. This satellite has real stereoscopic capabilities, as a wide range of incidence angles are available (range from 20° to 50°). It allows for the creation of large scale DEMs (nearly 100 km by 100 km), with a theoretical height accuracy better than 10 metres. In order to process these stereoscopic data the authors added to the digital cartographic workshop developed by GEOIMAGE a radargrammetric module. This module enables to automatically generate DEMs in a cartographic projection chosen by the user and create the associated ortho-images