Combining SAR tomography and a PSI approach for highresolution 3-D imaging of an urban area

Combining persistent scatterer interferometry (PSI) and SAR tomography approaches has the potential to overcome layover scenarios in urban areas and may thus increase the level of detail of differential interferometric measurements of displacements in such environments. In this paper, we report the current status and results of our efforts to integrate SAR tomography into an operational interferometric point target analysis (IPTA) processing tool as an extension to the conventional persistent scatterer interferometry approach. In particular, the PSI and the SAR tomography processing approaches applied are highlighted. In addition, details in the form of tomographic slices of two high-rise buildings are presented as well as a 3-D point cloud reconstruction of parts of the city of Barcelona are shown, as extracted from an interferometric stack of high-resolution stripmap-mode SAR data at X-band acquired by the TerraSAR-X spaceborne SAR sensor.