3D analysis of scattering effects based on Ray Tracing techniques

The side-looking geometry of SAR sensors hampers the interpretation of SAR images of urban areas. Simulation tools for illuminating 3D models of man-made objects by means of a virtual sensor support the interpretation of scattering effects by providing artificial images in the azimuth-range plane. In this paper, a simulation approach is presented which extends SAR simulation to three dimensions in order to focus detected intensity contributions in azimuth, range and elevation. Based on the simulation output, a concept for creating scatterer histograms displaying the number of scatterers within one resolution cell is introduced. Methods for analyzing simulated elevation data by means of selected slices are presented for an urban test site. Eventually, the number of scatterers extracted for a selected pixel by tomographic analysis, using a stack of spotlight TerraSAR-X images, is confirmed by results provided by the simulator.