Rapid geometric correction of SSC TerraSAR-X images with direct georeferencing, global DEM and global geoid models

Abstract

In this paper a process for rapid geometric correction of slant range SAR images is presented. The process is completely independent of ground control information thanks to the direct georeferencing method capabilities offered by the TerraS AR-X sensor. The process is especially rapid due to the use of readily available global DEMs and global geoid models. An additional advantage of this process is its flexibility. If a more accurate local DEM or local geoid model is readily available it can be used instead of the global DEM or global geoid model. The process is applied to geometrically correct a SSC TerraSAR-X image over a sub-urban mountainous area using the SRTM and the ASTER global DEMs and the EGM2008 global geoid model. Additionally two local, more accurate DEMs, are used. The accuracy of the process is evaluated by independent check points.