Bridge Detection in multi-aspect high-resolution Interferometric SAR Data

Abstract:
State-of-the-art airborne SAR sensors provide spatial resolutions in the order well below half a meter. In such data many features of urban objects can be identified, which were beyond the scope of radar remote sensing before. Core elements of urban infrastructure are bridges. An example for the new quality of the appearance of bridges in high-resolution InSAR data is given and interpreted. Due to the fine level of detail even smaller bridges are mapped to extended data regions covering large numbers of pixels. Therefore, in data of this quality the identification of bridge structure details is possible at least by visual interpretation. In this paper, the special appearance of bridges over water in high-resolution InSAR data is discussed. Geometric constraints for the mapping of bridge structures into the interferometric SAR imagery are given. These constraints can be exploited for the extraction of structural object information from the data. An approach for detection of bridges is proposed and first results demonstrated using orthogonal InSAR data sets of spatial resolution better than 40cm.