GB-InSAR Special Issues during its Applications on DEM Generation

Ground-based interferometric synthetic aperture radar (GB-InSAR) technology is becoming an important terrain mapping technology as it has the characteristics of short observation intervals, flexible operation environment and high data precision. Compared with air/space borne InSAR system, GB-InSAR has a wide beam, a scene breadth comparative to the slant range, and a large downwards-looking angle. The observation scenes always show the type of slope terrain with various gradients and slope orientations. Those particularities will bring new problems in DEM generation method and interferogram processing during its typical applications. Among them, the interferogram gaps caused by the shadow and weak reflections are always appear in mountainous or open-pit areas. Thus, in order to make the full use of the interferogram, a modified phase compensation and phase unwrapping method are proposed. Besides, the DEM generation method also need modification to adapt with the huge-azimuth, short-range area. In Section IV, the experimental results are shown to give a specific description of GB-InSAR applications characteristics and verifying the correctness and effectiveness of the proposed method.