不同插值方法下重力场模型的似大地水准面构建精度分析

Accuracy Analysis of Quasi Geoid Construction for Gravity Field Models under Different Interpolation Methods

摘要: 因高程系统和GPS系统的坐标基准不同，导致GPS高程无法直接应用到水准成果。常规的方法是通过数学模型进行高程异常拟合，但纯数学模型难以满足三等和四等水准的精度要求。使用EGM2008重力场模型的三种插值方法计算中长波，使用数据模型拟合短波，能够有效提高高程异常拟合精度。经过计算，三种插值方法的双二次插值法精度最高，4个检核点的绝对误差达到3.3 cm以内。

Abstract: Due to the different coordinate benchmarks between the elevation system and the GPS system, GPS elevation cannot be directly applied to leveling results. The conventional method is to fit elevation anomalies through mathematical models, but pure mathematical models are difficult to meet the accuracy requirements of the third and the fourth order levels. Using three interpolation methods of the EGM2008 gravity field model to calculate medium to long waves and fitting short waves with a data model can effectively improve the accuracy of altitude anomaly fitting. After calculation, the biquadratic interpolation method of the three interpolation methods has the highest accuracy, with an absolute error of within 3.3 cm for the four checkpoints.