GPS水准点优化选择法.PDF

GPS 水准点优化选择法 沈云中 , 高达凯 , 张兴福 ( 同济大学 , 上海 　200092) 摘要 : 水准联测点的选择对 GPS 高程拟合结果有显著影响 , 本文探讨了水准联测点的优化选择问 题 , 着重研究了以拟合误差最小为目标函数的水准联测点优化方法。给出了选择 GPS 水准联测点的 两种方法 , 其一是在所有 n 个 GPS 点中选择 m 个联测点的全组合方案 , 计算其拟合误差 , 选择误 差最小的联测方案 ; 其二是剔除法 , 即从 n 个 GPS 点中逐个剔除对精度贡献最小的水准联测点 , 一直剔到剩下 m 点为止。两个算例的结果表明 : 两种方法得到的 GPS 水准点是一致的 , 且确实获 得了最小的拟合误差。 关键词 : GPS ; 高程拟合 ; 优化选择 中图分类号: P2284 文献标识码 : B Abstract : The distribution of GPS level points will significantly influence the accuracy of GPS height interpolation. This paper probes into the optimal choice of GPS level points , especially in the criteria of minimizing interpolation error. Two methods for selecting the GPS leveling points are given here. The first method is to compute the interpolation error of total combination scheme for choosing m level points for n GPS points , and the scheme with minimum interpolation is taken as the optimal scheme. The second method is to eliminate GPS point that has the least contribution to the interpolation accuracy , and the GPS points will be eliminated according to this rule until remnant points number equal to m , which are selected as GPS level points. The results of the both cases show that the two methods get the same answer , and the minimum interpolation error can be realized. Key words : GPS ; height interpolation ; optimal choice GPS 网的起始大地高就可求出各 GPS 点相对起始点 1 　前言 精确的大地高 H , 联测水准的 GPS 点又可得到其正