GPS/水准点数对似大地水准面再精化结果精度分析

The Accuracy Analysis of GPS/Leveling Points on the Results of Quasi-geoid Refining

似大地水准面的精度直接决定了RTK用户获得我国1985国家高程基准成果的精度。论文利用4种不同精度的重力似大地水准面成果以及一定数量的GPS/水准点成果,通过移去恢复法和拟合内插方法详细分析了GPS/水准点数对区域似大地水准面再精化结果的影响,并利用实测数据进行验证。结果表明,GPS/水准点数量的增加可提高再精化水准面精度,但精度达到一定量级后,不再提高。此外,一定精度范围的初始水准面精度对于水准面再精化最终结果精度影响不大,与离散程度成反比。论文结论对今后区域似大地水准面再精化工作中方案的选择、成本的节约等方面有一定的指导意义。

The precision of the quasi geoid directly determines the precision of the China vertical datum of 1985 for RTK users.The effects of GPS/leveling points on re-refining leveling surface are analyzed in detail by using four different precision results of gravity quasi-geoid and a certain number of GPS/leveling points through the methods of removing recovery and fitting interpolation,and verification with measured data.Several conclusions have been drawn as follows:Increasing the number of GPS/leveling points can improve the precision of refining quasi-geoid,but when the precision reaches a certain magnitude,it will not improve any more.In addition,the initial quasi-geoid accuracy within a certain range of accuracy has little effect on the final result accuracy of quasi-geoid re-refining,which is inversely proportional to the degree of dispersion.The conclusion of the paper has certain guiding significance for the selection of scheme and cost saving in the future regional quasi-geoid re-refining work.