Automated CAD Model Based Geo-Referencing for High- Resolution SAR Data Fusion in Urban Environments

Fusion of SAR and optical images has to cope with the different imaging properties of both sensor types. In order to allow a meaningful data fusion, highly accurate geo-referenced images have to be provided. Based on CAD models of buildings, for example from available 3D-city models, simulated SAR images can be created using a SAR simulator. The correspondence between images of buildings created from a SAR simulator and the respective sections of unreferenced SAR images provides the required control point information. Using this approach an accurate geo-referencing can be achieved. The error in the initial reference of about 150m is reduced to around 1,5m. Even more, possible differences between the simulated image and the real image can be used for change detection applications.