BDS/GPS双模静态PPP定位精度与收敛性分析

Analysis of positioning accuracy and convergence of BDS/GPS dual-mode static PPP

随着仪表引导系统(instrument guidance system,IGS)精密星历实时化计划的推进,全球导航卫星系统(Global Navigation Satellite System,GNSS)精密单点技术已成为精密定位领域的一个热点。文章实现了北斗卫星导航系统/全球定位系统(BeiDou Navigation Satellite System/Global Positioning System,BDS/GPS)双模静态精密单点定位(precise point positioning,PPP)算法,并采用武汉大学发布的15 min精密卫星轨道与5min钟差产品对亚太地区多个测站实测数据进行BDS/GPS单模与双模静态PPP精度与时间收敛性的分析。从亚太地区多个测站的分析结果得出:BDS静态PPP充分收敛后的水平精度优于5cm,且北向精度优于东向,高程精度略差,优于10cm;对于收敛性,水平方向收敛速度快于高程方向,整体上为70~250个历元,BDS静态PPP定位结果逐渐收敛,但是天向存在收敛不充分现象;相对于GPS,目前BDS的PPP精度和收敛性比GPS略差,但充分收敛后目前可实现厘米级的绝对定位;BDS/GPS双模静态PPP收敛性优于单模,定位精度与GPS单模相当。

With the development of instrument guidance system（IGS） precise ephemeris real-time plan, Global Navigation Satellite System（GNSS） precise point technology has become a hot field of precision positioning. In this paper, the static precise point positioning（PPP） algorithm of BeiDou Navigation Satellite System/Global Positioning System（BDS/GPS） dual-mode is realized, together with the anal- ysis of the precision and time convergence of BDS/GPS single-mode and dual-mode static PPP for mul- tiple stations in the Asia-PaCific region with the 15 min precision satellite orbit and 5 min clock prod- ucts provided by Wuhan University. The analysis results show that with full convergence, the hori- zontal precision of the BDS static PPP is better than 5 cm, and the precision of the North is superior to that of the East, the vertical precision is better than 10 cm, slightly worse in contrast. For conver- gence, the horizontal convergence is faster than that of vertical direction. On the whole, the result of BDS static PPP positioning is converged gradually in the horizontal direction after 70-250 epochs while the insufficient convergence occurs in the vertical direction. Although the precision and convergence of BDS static PPP is slightly worse when compared with GPS, it can realize cm-level absolute positioning after full convergence. The convergence of BDS/GPS dual-mode static PPP is better than that of sin- gle-mode while the positioning precision is equal to that of GPS single-mode.