利用IKONOS立体像对提取南极菲尔德斯半岛地区DEM及其精度分析

DEM GENERATION AND ANALYSIS OF FILDES PENINSULA USING IKONOS STEREO PAIRS

本文讨论了IKONOS立体像对提取南极菲尔德斯半岛地区的DEM及其精度情况。由于IKONOS不提供基于共线模型所需的卫星星历参数,而提供基于有理函数(RPC)的近似模型,因此点位精度和高程精度主要由RPC模型精度来决定。直接使用RPC模型对参考级(Reference)产品进行DEM提取,其点位精度和高程精度为25m(CE90)、22m(LE90),这种精度不能满足高精度制图的要求。为了提高精度,利用中国第23次南极考察队(2006/2007)采集的控制点对RPC模型进行修正。通过对比分析表明DEM精度明显提高,影像和DEM分别能满足1∶5000比例尺遥感平面图制图要求和1∶10000比例尺地形图制图要求。

The paper mainly addresses DEM generation and analysis of the Fildes Peninsula using IKONOS stereo pairs. IKONOS uses the Rational Polynomial Camera（RPC） model, also called an Image Geometry Model（ICM） , as a substitute of rigid geometrical model based on the collinearity equation. The horizontal and vertical accuracies of generated DEM are mainly dependant on the accuracy of RPC model. By only using RPC model, the positional accuracy and vertical accuracy of reference product suite are 25m （CE90） and 22 m （LE90） respectively, which can＇ t meet the requirements of high accuracy topographic map. In order to improve the accuracy, the ground control points collected during CHINARE-23,2006/2007, are used to revise the previous RPC model. It reveals that the accuracy of extracted DEM improves apparently, which can meet the requirements of 1：5000 remote-sensing cartographic map and 1：10000 topographic map.