Utilization of lidar dem for SAR image analysis in dense urban areas

The increasing resolution of SAR data opens the possibility to utilise this data for scene interpretation in urban areas. Different SAR specific phenomena like foreshortening, layover, shadow and multipath-propagation burden the interpretation. For many urban areas detailed additional information is available which can support both the mission planning and the analysis of the acquired SAR data afterwards. In this paper a high resolution LIDAR DEM is incorporated to investigate the impact of the phenomena on the visibility of scene objects by a SAR measurement from a given sensor trajectory and orientation in an urban environment. This kind of ground truth is well suited for this task because it contains elevation information of every object in the scene. Shadow and layover areas are simulated by incoherent sampling of the DEM. By a variation of viewing and aspect angles a large number of such simulations are carried out. From this set of segmentations the n best are determined according to two example tasks, namely the analysis of objects on roads and the detection and reconstruction of buildings. The locations of the roads and the buildings are extracted from a GIS.