北斗精密定轨精度评估及站点分布影响分析

Accuracy Assessment of BDS Precision Orbit Determination and the Influence Analysis of Site Distribution

北斗精密轨道确定是北斗系统应用的一项关键内容,基准站数量和分布情况是影响定轨精度的重要因素。本文基于国际GNSS服务组织(International GNSS Service,IGS)多系统实验网(multi-GNSS experiment,M-GEX)站和中国区域的基准站共123站进行北斗精密定轨,得到目前较高精度的北斗精密轨道:GEO、IGSO和MEO卫星的定轨精度(1DRMS)为10.3 cm、2.8 cm和3.2 cm,径向精度均优于2 cm。在此基础上分析了中国区域基准站对北斗定轨的贡献,结果表明加入中国区域基准站后,重叠弧段精度平均提高了17.6%,其中IGSO卫星精度提高了36.3%。采用ODOP值和SLR检核方法进一步分析后发现,ODOP改善趋势、SLR检核精度提高程度与重叠弧段精度一致。

BDS precision orbit determination is a key content of the BDS application,and the number and distribution of reference stations are important factors affecting the accuracy of the orbit determination.In this paper,the BDS precise orbit determination results are obtained by using the IGS MGEX stations and the national reference stations in China.The accuracy of orbit determination of GEO,IGSO and MEO is 10.3 cm,2.8 cm and 3.2 cm,and the radial accuracy is better than 2 cm.The results show that the accuracy of the overlapping arcs is increased by 17.6% after adding the national reference stations in China,and the accuracy of IGSO satellite is improved by 36.3%.The results of ODOP and SLR were further analyzed.It was found that the improvement of ODOP improved area and SLR was consistent with the accuracy of overlapping arc.