Impact of orbital parameters on DEM production by SAR interferometry

The authors are interested to the impact of the orbital parameters on interferometric height calculated in range geometry. They use their exact formulation (Abdelfattah, 98), given the mathematical dependency of the interferogram phase and the target height, in order to extract an analytical estimation of the required orbital parameters accuracy for DEM generation. They propose a quantitative assessment of the effects of a variation in range position, baseline and interferometric phase on the topography. Results of analysis of these effects applied to a test site in Tunisia are presented. They also illustrate the effects by means of SIFI interferometric simulator that they had implemented for this purpose. They demonstrate that uncertainties on orbital parameters, and specially the range baseline component, induce an important errors on topography estimation. These errors, which depends linearly with slant range, could be corrected by using some reference points