北斗卫星导航系统空间信号测距误差评估

Evaluation of signal-in-space range errors of BeiDou navigation satellite system

针对北斗卫星导航系统空间信号测距误差能否满足公开服务性能需求的问题,该文顾及卫星轨道误差和卫星钟误差影响的北斗卫星导航系统空间信号测距误差评估方法,利用MGEX提供的北斗广播星历和GFZ提供的事后精密星历,对2018年1月北斗卫星的广播星历误差、轨道误差和空间信号测距误差进行了短期分析评估。结果表明,所有北斗卫星在评估期内的空间信号测距误差精度为2.11 m,满足北斗系统公开服务空间信号性能需求。其中,MEO卫星空间信号测距误差精度最高,为1.43 m,GEO卫星精度最差,为2.62 m;所有卫星的空间信号测距误差总体上优于2.5 m,空间信号测距误差呈1 d周期变化;在变化趋势上,MEO空间信号测距误差变化比较稳定,而GEO和IGSO存在一定的跳变情况。

Aiming at the problem that whether the URE of BDS could meet the performance requirements of the open service,the evaluation method of URE of BDS was introduced,which was based on the influence of satellite orbit error and satellite clock error. The broadcast ephemeris error,orbit error and URE were analyzed in a short-term based on the broadcast ephemeris provided by MGEX and precision ephemeris provided by GFZ in January 2018. The results showed that the accuracy of URE of all satellites during the evaluation period was 2.11 m,which satisfied the performance requirements of BDS open service space signal. The MEO satellite URE had the highest accuracy of 1.43 m,and the GEO satellite had the worst accuracy of 2.62 m. The URE of all satellites was better than 2.5 m,and the URE changed by day cycle. In the trend of change,the MEO changes were relatively stable,while GEO and IGSO had certain jumps.