BDS实时精密单点定位性能分析

Performance Analysis of BDS Real-time Precision Point Positioning

以GFZ事后精密轨道与钟差产品为参考,评估CNES实时轨道与钟差精度。基于CNES实时轨道和钟差,对18个MGEX地面站进行了实时精密单点定位(Real-Time Precise Point Positioning, RT PPP)测试,以GPS为参考分别对比分析了BDS3、BDS2+3的RT PPP的性能。结果表明,GPS实时轨道三维精度优于11 cm,实时钟差精度约为0.02~0.06 ns, BDS非GEO卫星实时轨道三维精度优于33 cm,钟差精度约为0.05~0.29 ns。BDS与GPS三维定位精度基本相当,约为5~6 cm。GPS平均收敛速度约为59 min, BDS平均收敛时间约为124 min。相对于BDS3、BDS2+3在E、N、U三方向的定位精度分别提升9.9%、6.7%、2.6%,3D定位精度提升5.8%,收敛速度提升20.2%。

Using GFZ post-event precision orbit and clock offset products as a reference,CNES real-time orbit and clock offset accuracy are evaluated.Based on CNES real-time orbit and clock offset,Real-Time PPP positioning tests are conducted on 18 MGEX ground stations,and the performance of BDS3 and BDS2+3 RT PPP is compared and analyzed using GPS as a reference.The results show that the GPS real-time orbit 3D accuracy is better than 11 cm,and the real-time clock offset accuracy is about 0.02~0.06 ns.The BDS non GEO satellite real-time orbit 3D accuracy is better than 33 cm,and the clock offset accuracy is about 0.05~0.29 ns.The three-dimensional positioning accuracy of BDS and GPS is basically equivalent,about 5~6 cm.The average convergence speed of GPS is about 59 min,and the average convergence time of BDS is about 124 min.Compared to BDS3,the positioning accuracy of BDS2+3 in the E,N,and U directions has been improved by 9.9%,6.7%,and 2.6%,respectively.The 3D positioning accuracy has been improved by 5.8%,and the convergence speed has been improved by 20.2%.