不同分析中心GNSS实时SSR产品研究与分析

Analysis on multi-GNSS SSR products from different analysis centers

为了弥补以往实时轨道和钟差产品的评估大都围绕全球定位系统(GPS),而对多个卫星导航系统的实时产品研究分析还不够全面的不足,研究分析了不同分析中心的实时状态空间表达(SSR)产品:给出实时产品与广播星历匹配、实时精密轨道和钟差恢复的算法;评估分析了4个卫星导航系统的卫星实时轨道、钟差精度和实时轨道跳跃现象;最后通过设计仿动态实验,分析评估产品的实时精密单点定位性能。结果表明:除北斗卫星导航系统(BDS)静止轨道卫星外,其他导航卫星的实时轨道精度都达到了厘米级,实时钟差精度达到亚纳秒级,这表明各分析中心实时卫星产品与钟差产品的质量和时效性不断提高;与事后精密轨道相比,实时轨道会发生周期性的跳跃,跳跃周期与超快速星历更新周期一致。

In order to make up for the deficiency in researching and analyzing the real-time products for multiple navigation satellite systems due to the traditional evaluation of real-time orbit and clock error products mostly around Global Positioning System(GPS),the paper studied on the real-time State Space Representation(SSR)products from different analysis centers:the algorithms of SSR products matching with broadcast ephemeris and recovery of real-time precise orbit and clock difference were given;and the real-time orbits of four navigation satellite systems,clock error accuracy and the slip phenomenon of realtime orbit were evaluated and analyzed;finally a dynamic simulational experiment was carried out to assess the performance of real-time Precise Point Positioning(PPP)for the products.Result showed that:the real-time orbit accuracy of most satellites could reach centimeter level and the real-time clock error reaching sub-nanosecond level except BeiDou navigation satellite System(BDS)geostationary Earth orbit satellites,indicating the increase of the quality and timeliness of the real-time satellite and clock error products from different analysis centers;moreover,compared with the post-precise orbit,the real-time orbit would have periodic slips,and the slip period would be consistent with the update period of ultra-rapid ephemeris.