BLOCK ADJUSTMENT WITH AIRBORNE INSAR FOR HIGH-PRECISION DEM EXTRACTION

Block adjustment can improve the accuracy of airborne InSAR data which covers large areas under the conditions of sparse control points, and it can improve the planar and vertical accuracy using a few of gound control points (GCPs). In this paper, we research the orthogonal decomposition of look vector model, three dimensional reconstruction model for airborne InSAR and the sensitivity equations at first. Secondly, we analyze the error sources and adjustment parameters for the Chinese airborne InSAR system of Chinese Academy of Surveying and Mapping SAR (CASMSAR). Finally, InSAR block adjustment method has been proposed for the airborne CASMSAR system, and the DEM is directly extracted. Experiments are carried out with X-band interferometric data acquired by CASMSAR system, and the effectiveness and practicability of the process method are verified. It can be seen from this article the results met the requirements of topographic mapping for the scale of 1: 10000 in China.