基于Bursa模型的地球重力场模型2008高程异常误差算法

A Height Anomaly Error Algorithm of Earth Gravitational Model 2008 Based on Bursa Model

针对地球重力场模型2008(EGM2008)根据点位经纬度求得的高程异常精度较差,且测区内校正用已知点难以就近获得的问题,提出一种以Bursa模型求解EGM2008高程异常误差的算法;基于Bursa模型可进行严密高程转换的特点,利用测区外已知点求解的转换参数对测量点进行EGM2008高程异常误差值解算;以验算实例和不同区域工程实例对比的方式对该算法进行验算,结果表明:所提算法解算的高程异常误差值可作为EGM2008高程异常误差的修正值,利用远距离已知点校正高程异常可得到图根级精度的高程成果,且能适应不同地形、地势的工程测量要求。

To solve the problem that the accuracy of height anomaly calculated by Earth Gravity Model 2008(EGM2008)was poor according to the longitude and latitude of the point,and it was difficult to obtain the known points nearby in the calibration area,a height anomaly error algorithm of earth gravitational model 2008 by using Bursa model was proposed.Based on the feature of Bursa model for precise height conversion,the conversion parameters obtained by the known points outside the survey area were used to calculate the height anomaly error values of EGM2008 for the survey points.The algorithm was validated through examples and comparisons with different regions,and the results show that the eleva-tion anomaly error calculated by the proposed algorithm can be used as the correction value of elevation anomaly error of EGM2008,and the height results with root-level accuracy can be obtained by using the known points at a long distance to correct the height anomaly,and it can adapt to the engineering survey requirements of different landform and terrain.