北斗三号实时精密轨道钟差估计及精度效率评定

Real-time Precise Orbit and Clock Estimation for BDS-3 Constellation:Accuracy and Efficiency Assessment

作为中国自主研发的全球卫星导航系统,北斗卫星导航系统的建设从一开始就确定了三步走的战略。围绕精度和效率等性能指标,进行了几项试验以确定一个合适的地面跟踪网。结果表明,在已有60个测站的情况下,增加跟踪站的数量并不能继续提高北斗三号轨道和钟差产品的精度。进一步的精度提升应该更依赖于天线相位中心改正缺失和太阳光压模型不完善等模型缺陷问题的解决。

BeiDou navigation satellite system(BDS)is an independent global navigation satellite system(GNSS)developed by China.The three-step strategy was adopted from the very beginning and the third and final step,BDS-3,had been officially announced operational on July 31,2020.An essential and necessary task is to generate precise orbit and clock products in real time,only in this way can BDS-3 constellation be ready for widespread use from ordinary to high-precision real-time applications.In this work,keeping accuracy and efficiency in mind,several experiments are conducted to find an adequate size of tracking networks.It is shown that,up to 60 stations,the accuracy of BDS-3 orbit and clock products can not be improved by increasing the number of tracking stations.Further accuracy improvements should depend on solving some modelling defects such as lack of antenna phase center corrections and imperfection of solar radiation pressure models.