BDS/GPS PPP固定解精度分析及其在地震中的应用

Precision analysis of BDS/GPS PPP fixed solution and its application in earthquake

为了提高北斗卫星导航系统(BDS)和全球定位系统(GPS)精密单点定位(PPP)性能,提出一种BDS/GPS PPP固定解精度分析方法:采用无电离层组合PPP模型,给出基于未校准相位延迟(UPD)估计的PPP模糊度固定(AR)方法;并分析将动态PPP AR应用于估计地震中全球卫星导航系统(GNSS)测站位移量的可行性。实验结果表明,UPD产品估值相对稳定,利用该UPD产品可实现BDS/GPSPPPAR,提高PPP定位性能,其中,BDS/GPS组合动态PPP收敛时间在东(E)、北(N)和天(U)方向上分别为15、12.5和20min,其固定解在3个方向上的定位精度可达1.52、1.34和2.81 cm,较浮点解分别提升12.6%、5.6%和9.4%;利用BDS/GPS动态PPP AR分析青海地震中清水河站(QSHZ)测站位移量,验证了BDS/GPS PPP AR可实现厘米级地震位移监测。

In order to improve the precise point positioning(PPP)performance of BeiDou navigation satellite system(BDS)and global positioning system(GPS),the paper proposed a precision analysis method of BDS/GPS PPP fixed solution:a combined PPP model with ionospheric-free was used,and a PPP ambiguity resolution(AR)method based on uncalibrated phase delay(UPD)estimation was given;then the feasibility of applying kinematic PPP AR to estimate the displacement of global navigation satellite system(GNSS)stations in earthquakes was analyzed.Experimental results showed that the valuation of UPD products would be relatively stable,and BDS/GPS PPP AR could be realized by using the UPD product,which helps improve the PPP positioning performance.Among them,the convergence time of BDS/GPS combined kinematic PPP in East(E),North(N)and Up(U)directions would be 15,12.5 and 20 min,respectively.Moreover,the positioning accuracy of the fixed solution in three directions would be 1.52,1.34 and 2.81 cm,and compared with the floating solution,the improvement rates would be 12.6%,5.6%and 9.4%,respectively.Finally,it was verified that BDS/GPS PPP AR could realize cm-level seismic displacement monitoring by using BDS/GPS kinematic PPP AR to analyze the displacement of the Qing Shui He Zhan(QSHZ)station during the Qinghai earthquake.