北斗三号码观测值评估及定位精度分析

Code observation evaluation and positioning accuracy analysis of BDS-3

随着北斗卫星导航系统(BeiDou Navigation Satellite System,BDS)完成全球组网,北斗三号(BDS-3)3个新频段观测值和定位精度需要评估。文章选取全球范围20个国际GNSS服务(International GNSS Service,IGS)组织的监测站数据,从信噪比(signal-to-noise ratio,SNR)、伪距多路径(multipath,MP)误差和伪距定位误差方面综合对比BDS-3的6个频段码观测值数据。结果表明:6个频段的SNR从大到小依次为B2a+b、B3I、B2a、B2b、B1C、B1I;6个频段的伪距MP误差从小到大依次为B2a+b、B2a、B3I、B1C、B2b、B1I;B3I频段观测值定位精度最高,B2a+b、B2a频段定位精度相当,且优于B1C频段;目前接收机跟踪BDS-3新频段的可见卫星数相对较少,独立解算时误差较大,稳定性较差。研究结果可为BDS-3应用和发展提供参考。

With the successful construction of BeiDou Navigation Satellite System(BDS),the observations and positioning performance of the three new frequency bands of BDS-3 need to be further evaluated.In this paper,data from 20 International GNSS Service(IGS)monitoring stations around the world are selected.The signal-to-noise ratio(SNR),pseudorange multipath(MP)error and pseudorange positioning error of six frequency band codes observations of the BDS-3 system are analyzed.The results show that the SNR of the six frequency bands from large to small is:B2a+b,B3I,B2a,B2b,B1C,and B1I;the pseudorange MP error of the six frequency bands from small to large is:B2a+b,B2a,B3I,B1C,B2b,and B1I;the B3I frequency band observation has the highest positioning accuracy.The positioning accuracy of the B2a+b and B2a frequency bands is at the same level and significantly better than that of the B1C frequency band.Currently,there are relatively few satellites tracked by the receiver,and the accuracy and stability are relatively poor when positioning independently.The research results can provide reference for the application and development of BDS-3.