对流层映射函数对精密单点定位的影响分析

摘要

Observations of IGS stations in different latitude areas in north and south hemisphere are computed in order to analyze the influence of tropospheric mapping functions on Precise Point Positioning (PPP).Differences of PPP coordinates and daily SNX file coordinates issued by IGS and PPP coordinates between models are compared.Finally,the influence on the difference between models by seasons are analyzed.T he result show s that three mapping functions can improve the PPP precision,in w hich the difference is small,GM F and VM F1 have the similar influence on the PPP precision,and both are better than NMF.In different seasons,the difference between models will change in the form of mm.%分析对流层映射函数(NM F、VM F1和GM F)对精密单点定位(PPP)精度的影响,对分布于南北半球不同纬度地区的IGS跟踪站的观测数据进行解算.首先比较PPP坐标与IGS发布的日解SNX文件坐标差异和模型间PPP坐标差异,然后分析不同季节对模型差异的影响.实验结果表明,3种映射函数均可提高 PPP精度,精度控制在1 cm左右.整体而言,VM F1和GM F对PPP精度的影响相当,且优于NM F.在不同季节里,模型差异会发生mm级的变化.