A radargrammetric orientation model and a RPCs generation tool for COSMO-SkyMed and TerraSAR-X high resolution SAR

The topic investigated in this paper is the stereo imagery orientation with regards to the SAR imagery in zero-Doppler geometry acquired by COSMO-SkyMed and TerraSAR-X in Spotlight mode. A rigorous orientation model, based on geometric reconstruction, had been already implemented in the scientific software SISAR; starting from this model, a tool for the Rational Polynomial Coefficients (RPCs) generation has been developed. The results of the orientation tests, performed using both rigorous and RPCs models, clearly show that the generated RPCs exploit the geometric potentialities of SpotLight stereo pairs as regards 3D surface reconstruction at the same accuracy level (about 3 meters) of the rigorous model.