基于GPS实测控制点的SPOT 5 1A数据几何校正方法精度比较

GEOMETRIC CORRECTION METHODS OF SPOT 5 1A DATA BASED ON GPS-MEASURED GROUND CONTROL POINTS

采用高精度的星基差分GPS实测控制点对SPOT5 1A数据几何校正方法进行比较,对校正误差的产生原因进行分析。结果表明:正射模型法的校正精度远高于多项式法的校正精度;多项式法在X方向上的误差远大于Y方向上的误差;正射模型法的误差在2个方向上差别不大。卫星扫描角度引起的像元畸变是多项式方法产生较大误差的重要原因。

Using the high resolution ground control points measured by satellite -based DGPS （Differential Global Positioning System）, this paper compared two geometric correction methods for SPOT 5 1A data and analyzed the causes of correction errors. The results show that the accuracy of the orthorectification model method is better than that of the polynomial method. The errors of the polynomial method in Y axis are bigger than those in X axis, but the error difference in Y axis and in X axis is not obvious for the orthorectification model method. The pixel distortion caused by the satellite observation angle is the main cause for the bigger errors of the polynomial method.