Absolute Phase Estimation from TerraSAR-X Acquisitions using Wideband Interferometry

Abstract

Estimation of topography for the generation of digital elevation models requires unwrapping of the interferometric phase to obtain the absolute phase. When the topography changes rapidly or the geometry is unfavourable, phase unwrapping cannot always be performed correctly leaving gaps or errors in the digital elevation model. Based on taking the differential phase between two subband interferogramsn, the delta-k technique can artifically increases the height of ambiguity by up to several orders of magnitude. This renders phase unwrapping unnecessary and directly provides the absolute phase. Here we present some preliminary results demonstrating the application of delta-k interferometry to TerraSAR-X data.