中文摘要：

在地形起伏较大的山区用于涉SAR生成DEM时，合适的入射角是获取高精度DEM的重要参数之一。本文基于ENVISAT／ASAR多角度干涉雷达数据，SRTM90米分辨率的DEM以及1：5万的数字化DEM数据，从定性和定量的角度比较和分析了干涉SAR在获取山区DEM时，入射角对DEM精度的具体影响。结果表明：对于ASAR的多入射角干涉雷达数据，在不同入射角条件下由于雷达叠掩和透视收缩的影响，获取的DEM精度差别很大，入射角带来的影响相当显著，比如IS2和IS4角度得到的DEM的精度差超过了6米。因此，在山区干涉SAR地形成图时，必须对入射角的大小进行严格的选择。

英文摘要：

With the successful implementation of ERS-1/2 tandem and SRTM project, InSAR has been wildly used for topographic mapping; in addition, the new global topographic mission such as TanDEM-X project is ongoing. In this paper, firstly, the impact of incidence angle on interferometric SAR DEM generation is detailed investigated from theoretical viewpoint; then, from the ENVISAT/ASAR multi-angle interferometric SAR data, the three DEMs of IS2, IS3 and IS4 swath images are generated using EvInSAR software of EarthView; finally, the impact of layover and foreshortening on DEM accuracy at different incidence angle are compared and analyzed from quantitative and qualitative viewpoints using SRTM DEM with 90m horizontal resolution and digital topographic DEM with 1 ： 50000 scale. The results indicate that ： （ 1 ） the impact of incidence angle on DEM generation is significant and large differences exist in the result DEMs due to radar layover and foreshortening at different incidence angle. For example, the difference is over 6m between the DEMs extracted from IS2 and IS4 swath images. So, the incidence angle must be strictly selected when using InSAR for DEM generation in the mountain area. （2） The decorrelation is significant with the 35-day temporal, which is in prejudice of the overall DEM accuracy evaluation. If the data with large incidence angle and no temporal decorrelation is obtained, the further study and analysis will be implemented from more general quantitative and qualitative viewpoints.