Radargrammetric DEM Extraction Over Urban Area Using Circular SAR Imagery

Digital elevation model (DEM) extraction in urban areas, using synthetic aperture radar (SAR) imagery, has become a subject of interest with the increased availability of high-resolution SAR images. One of the main advantages of SAR imagery is that, except from very peculiar situations, the radiometry of these images does not depend on weather conditions. The main drawback is the slant-range geometry which leads to large shadow and layover areas, and, therefore, to an incomplete DEM. In this paper, a new method of DEM extraction using SAR imagery acquired on a circular trajectory is proposed. Results are presented with data acquired with the SETHI system from ONERA, in X-band, in the city of Nîmes, France.