基于EGM2008模型的GPS高程网数据处理新方法

New Method of GPS Height Net Data Processing Based on EGM2008 Model

针对GPS只能测量大地高,且在山区或高程异常值差大的地区,GPS控制网高程平差将会受到高程异常值的影响,提出利用EGM2008模型计算GPS控制点高程异常值,将基线两端点的高程异常差值作为观测值的一部分直接参与平差。试验表明,该方法有效地提高了GPS高程网数据处理精度,文中的试验精度提高了一个数量级,减小了附合线路闭合差,但对环闭合差与观测值多余观测分量无影响。

According to the GPS only can measure the geodetic height,and in the mountains or the area with the big value of difference of height anomaly,the adjustment of GPS control network will be affected by height anomaly value. Using the EGM2008 model to calculate the abnormal height value of GPS control points is proposed,and the height anomaly difference value between the two endpoints of baseline as part of the observed value involves in the adjustment directly. The experiment shows that this method is effective to improve the precision of GPS height network data processing. The test precision in this paper improves one order of magnitude. It reduces the closure error of connexio line,but it doesn＇t influence the ring closure error and the observed value of redundant observation component.