利用SRTM以及DTM2006.0全球地形模型构建剩余地形模型(RTM)数据,并将其转换为RTM高程异常。通过GPS/水准点的优化选择法,选择少量GPS/水准点的实测高程异常,扣除EGM2008模型以及SRTM与DTM2006.0模型求得的剩余模型高程异常,对残余高程异常进行拟合,从而进一步提高GPS高程转换的精度。最后利用两个不同测区的高精度GPS/水准数据对此方法进行研究。结果表明:利用GPS/水准点的实测高程异常,扣除综合2160阶次的EGM2008模型以及SRTM/DTM2006.0剩余地形模型求得的高程异常,并对残余高程异常进行拟合,能显著提高GPS高程转换精度。
The RTM data can be constructed from SRTM and DTM2006.0 global digital terrain model,and RTM height anomaly are computed based on RTM data.Several GPS/leveling points are selected with optimal choice method for constructing the residual height anomaly interpolated model according to their measured height anomaly,EGM2008 height anomaly and RTM height anomaly,and then the accuracy of height anomaly can be improved.Finally two cases of GPS/leveling data are adopted,and the results show that the accuracy of GPS height transformation can be obviously improved using residual height anomaly interpolation based on measured height anomaly,EGM2008 model expanded to 2160 degree and order and SRTM/DTM2006.0 residual terrain model.