GPS高程拟合的方式及可靠性分析

在范围不大的区域中，高程异常具有一定的几何相关性，GPS高程拟合就是利用这一原理，求解正常高。在解析法求解过程中，首先用最小二乘法确定拟合数学模型的系数，在此基础上计算出待测点的高程异常值。通过实例验证：GPS高程拟合的精度主要取决于GPS大地高的精度、重合点正常高的精度、重合点的分布及拟模型的选择。一般在重合点数量充足且分布均匀的情况下，GPS高程拟合的精度可达到四等水准网的精度要求。

The Way and Reliability Analysis of GPS Height Fitting

In a moderate area,height anomalies usually have certain geometric relativity.GPS height fitting uses this principle to extract normal heights.During the analytic extracting process,to use the least square method determines parameters of fitting mathematical model first,then figures out height anomaly of surveying points.Through verification of living examples,the accuracy of GPS height fitting is mainly dependent on the accuracy of GPS geodetic height,accuracy of coincident point normal height,coincident point's distribution and fitting model selection.Generally,under the case of enough amounts and evenly distributed of coincident points,the accuracy of GPS height fitting can meet the requirement of the fourth order leveling network.