A comparison of phase to height conversion methods for SAR interferometry

SAR interferometry has been shown capable of producing accurate digital elevation models. InSAR height map generation always includes a transformation from the unwrapped phase to terrain height. Various methods for carrying out this step have been presented in the literature. This paper compares the different methods using both synthetic and real data for spaceborne and airborne geometries. The systematic errors introduced by each algorithm are analyzed. For each method, both the necessary number of parameters, as well as their required accuracies are evaluated with the goal of minimizing the required number of ground control points. The impact of the choice of geometry on the differential InSAR case is also investigated.