利用外部DEM辅助山区SAR立体像对匹配及地形制图  

Topographic Mapping in Mountainous Areas Using StereoSAR Assisted by External DEM

作　　者：贺雪艳[1] 张路[1] Timo BALZ 廖明生[1] 

机构地区：[1]武汉大学测绘遥感信息工程国家重点实验室,湖北武汉430079

出　　处：《测绘学报》2013年第3期425-432,共8页Acta Geodaetica et Cartographica Sinica

基　　金：国家863计划(2011AA120404);国家973计划(2013CB733205);国家自然科学基金(4127145;41174120;41021061)

摘　　要：SAR立体像对的匹配是利用雷达摄影测量技术提取地形高程信息的关键,匹配精度将直接影响结果 DEM的高程精度。针对山区SAR立体像对匹配过程中同名点选取困难的问题,引入外部粗分辨率DEM作为辅助数据,将该DEM高程转换为视差,为匹配提供初值,同时采用金字塔匹配策略,不仅可以缩小搜索范围,提高搜索效率,而且能够减少粗差的产生。试验结果表明,采用外部DEM辅助之后,匹配粗差点数量相对于传统的雷达摄影测量处理结果明显减少,从而有效地提高了高程信息提取重建的精度。Matching between stereo SAR image pairs is crucial for Radargrammetry to extract height information, and the matching accuracy will directly influence the accuracy of resultant DEM. The homologous points are difficult to identify in StereoSAR image pair due to complex geometric and radiometric distortions. In this paper, a new method is proposed to improve the matching performance. According to this method, an external DEM of coarse resolution is utilized as the auxiliary data from which the initial parallax can be derived to facilitate the step of image matching. At the same time, a pyramid delamination matching scheme is adopted to reduce the search range and thus improve the matching efficiency and control the propagation of gross errors, The experimental results show that the gross errors on the resultant DEM are reduced significantly with assistance of external DEM, and the derived elevation accuracy is improved effectively.

关 键 词：雷达摄影测量 视差模型 相关系数 金字塔匹配 外部DEM 

分 类 号：P237[天文地球—摄影测量与遥感]