卫星摄影三线阵CCD影像的EFP法空中三角测量(一)

系统地介绍了EFP法空中三角测量的基本思想、EFP像点坐标计算、平差的数学模型和卫生摄影测量的数字模拟,并以模拟数据进行了自由网＋控制点平差、外方位元素量测值参与平差、外方位元素量测值常差的分离以及区域平差等实验计算和实验结果分析。通过研究分析得出结论：（1）三条基线的航线可以保证三线阵CCD影像光束法平差的几何强度;（2）控制点可以布设在航线首末端,二线交会区的高程精度比三线交会区仅低约1.4因子;（3）外方位元素观测值是三线阵CCD影像光束法平差不可缺少的数据,经过平差可以不同程度地提高平差的高程精度。即使外方位元素观测值达到现代的精度,光束法平差的高程精度仍比直接前方交会高,所以三线阵CCD相机比单线阵、双线阵相机在全球性无控制卫星摄影测量或外星球摄影测量方面有更大的优势。

EFP Aerial Triangulation of Satellite Borne Three-line Array CCD Image

This paper completely introduces the basic idea of the EFP (Equivalent Frame Photo) aerial triangulation, EFP image point coordinate calculation and the function model of adjustment as well as the digital simulation of the satellite photogrammetry. Then, the free framework + the control points adjustment, the adjustment with the observations of the exterior orientation element, detection the constant error of the observations of the exterior orientation element and the block adjustment are calculated and analysed using the simulated data.Through experiment and analysis, the conclusions are: -The strip length of the three baselengths can be built up a stable model of the three-line array CCD image strip adjustment; -The control points can be arranged on the start and the end of the strip. The elevation accuracy of the twofold area is lower about a factor of 1.4 than the threefold area; -The observations of the exterior orientation element are the necessary data for the three-line array CCD image bundle adjustment. By the adjustment, the elevation accuracy can be improved in variant levels. Even if the accuracy of the observations of the exterior orientation elements are so high now, the elevation accuracy of the bundle adjustment is higher than the only forward intersection, so the three-line array CCD camera is more advantageous than single-line and double-line cameras in global satellite photogrammetry without control points or the exterior planet photogrammetry.