Radargrammetry and space triangulation for DEM generation and image ortho-rectification

In 2002 ENVISAT with the advanced SAR (ASAR) as one important instrument was launched. As compared to the preceding SAR sensors on ERS-1 and ERS-2 the ASAR has beam-steering capability permitting the acquisition of data over the same area under the different incidence angles as required by radargrammetry. In this paper a concept of combined use of radargrammetry and space triangulation to derive digital elevation models (DEMs) is presented. Space triangulation with opposite side acquisitions is used to determine a number of control points. Radargrammetry is then used to derive a DEM using these control points as reference. Preliminary test on the different steps of the combined method are presented.