顾及非格网数据考虑地形改正的GPS水准高程拟合

系统地分析了目前常用的确定高程异常的重力法和几何法在山区GPS网中的局限性。提出了一种顾及非格网数据考虑地形改正的GPS水准高程拟合法，同时对利用非格网数据和内插格网概略大地高所造成的影响也进行了估计。建议在地形起伏较大地区，借助地形图内插部分特征点作为虚拟GPS观测值，参与整体内插计算，有助于提高计算精度。

Height Determination with GPS Leveling Data Considering Non-grid Data and Effect of Terrain

In order to resove the normal. height of GPS nets in mountainous area, a new geometric methed considering terrain effect is discussed in this paper. The tnathematical medel of the new methed is also given. Besides, the accuracy of this methed using non-grid height's data is also analyzed. The effect of using non-grid data and inteoplation methed on calculating normal height is estimated. In order to improve inteoplation accuracy in the area where terrain changes very greatly, topographic map of GPS net is advised to use for practical application. Of course, net shape and number of GPS leveling points should also be considered in practical calculation. If the condition can t meet in practical wok, the correspond measurements are given in the paper. Using the new methed,a few of GPS nets in mountainous area have been tested in the paper. The result shows that the accuracy of this methed in mountainous area approximates as high as in smooth area. All these show that height determination with GPS leveling data considering non-grid data and effect of terrain valid in mountainous area.