顾及轨道误差的GNSS卫星钟差实时估计策略优化

为提高GNSS卫星钟差实时估计精度,针对GNSS各卫星系统的轨道差异,分析各系统卫星轨道误差对钟差估计的影响,基于距离函数线性化二阶残余项的思想,提出了一种顾及轨道误差的权函数模型,以优化实时卫星钟差估计策略。利用全球均匀分布的IGS和iGMAS跟踪站的实时观测数据进行实验,并与GBM的事后精密钟差进行对比分析。结果表明:GPS精度提高率为6.47%,BDS精度提高率为6.46%,GLONASS精度提高率为7.42%,Galileo精度提高率为7.62%。

Strategy Optimization of GNSS Satellite Clock Offset Real-time Estimation Considering the Orbit Error

In order to improve the accuracy of real-time estimation of GNSS satellite clock, the influence of orbit error of each system on the satellite clock offset estimation is analyzed considering the orbit differences of each system. And based on the idea of linearizing the second-order residuals of distance function, a weight function model taking into account orbit error is proposed to optimize the estimation strategy of real-time satellite clock offset. The experiments real-time clock offset is calculated by the IGS and iGMAS tracking stations, and compared with the final precision satellite clock offset provided by GBM. The results show that the accuracy improvement rates of GPS, BDS, GLONASS and Galileo are 6.47%, 6.46%, 7.42% and 7.62% respectively.