机载双天线InSAR(interferometric synthetic aperture Radar)是获取高精度数字高程模型(digital elevationmodel,DEM)的新技术。为了获取大面积高精度的DEM,在已有的应用机载InSAR数据生成DEM流程的基础上,引入精确干涉参数定标和区域网平差处理技术,提出了利用国产机载双天线InSAR数据生成丘陵地区大面积、高精度DEM的技术流程,主要包括干涉定标、干涉处理、区域网平差、相高转换、地理编码和影像镶嵌;基于VC++开发了InSAR地形制图处理系统。以四川江油试验区4个条带、76景高分辨率机载InSAR数据为基础进行试验研究,生成了覆盖超过500km。的高精度DEM。利用野外布设的角反射器检查点进行精度检验的结果是点位中误差为工人职员±1.188m,高程中误差为±0.508m。该结果表明:应用上述技术流程生成的DEM能满足丘陵地区1:1万比例尺一级高程中误差的精度要求;机载InSAR可作为复杂地区大面积地形测图制取的一种技术手段。
The airborne interferometric synthetic aperture Radar (InSAR) is a new technique for generating digital elevation model (DEM) with high accuracy. To generate high precision DEMs in large areas, this paper introduces accurate parameter calibration and bundle adjustment to the pre existing data processing flow of airborne InSAR DEMs generation, and presents a novel method and procedure for massive high precision DEMs generation by using airborne dual - antenna InSAR data of hilly areas, which includes parameter calibration, interferometric processing, bundle adjustment, phase -to -height conversion, geo coding and mosaicking. The airborne InSAR for the topography mapping processing system has been exploited based on the VC + +. Some experimental research is presented based on airborne dual - antenna X - band InSAR data of 4 stripes. The authors processed and generated a high precision DEM covering an area of over 500 km2. Several comer reflectors were placed in this area as reference GCPs for the assessment of the accuracy of the generated DEM. The evaluation results in terms of the mean square error (MSE) were derived by comparing the generated InSAR DEM with the reference GCPs. The MSE of the point and the height are +1. 188 m and -+0.508 m, respectively. It is concluded that the generated DEM using the proposed method meets the requirements of 1:10 000 terrain mapping. The airborne InSAR system could provide a new technique for topographic mapping in large complex areas.