光学卫星摄影无控定位精度分析

"全球连续覆盖"和"局部区域覆盖"是卫星摄影测量常用的两种摄影模式,两种模式应用目标和无控定位实现途径也各有特点。本文简要介绍了两种模式典型的卫星无控定位精度情况,阐述了光束法平差的关键技术,重点对前方交会和光束法平差无控定位精度进行试验分析。试验结果表明,姿态误差是影响无控定位精度的重要因素,影像分辨率对其影响较小。当外方位角元素误差大于0.5″时,即使影像分辨率为5m,光束法平差后,其无控定位精度也优于0.5m分辨率影像前方交会精度。

Analysis of Location Accuracy without Ground Control Points of Optical Satellite Imagery

There are two photography modes in optical satellite photogrammetry, including global continuous coverage and local area coverage, and each photography mode has its own characteristics about application and way to realize location accuracy without ground control points (GCPs).In this paper, the location accuracy without GCPs of typical satellite is introduced, and the key technical in bundle adjustment is described.Finally, the simulation experments are performed about location accuracy without GCPs using forward intersection and bundle adjustment.The results are shown: the attitude accuracy of exterior orientation elements is key factor to affect the location accuracy without GCPs, while the image resolution has little effect.When attitude accuracy of exterior orientation elements exceeds 0.5, the location accuracy without GCPs using bundle adjustment with 5 m resolution is better than it using forward intersection with 0.5 m resolution.