顾及频间偏差的GNSS多频非组合PPP变形监测

Deformation Monitoring with GNSS Multi-Frequency Uncombined PPP Considering Inter-Frequency Biases

精密单点定位(PPP)技术有望解决长距离、大范围等监测场景难以找到稳定基准点的难题。现代化的全球卫星导航系统(GNSS)卫星纷纷开始播发多频信号,多频观测值融合理论上可提升PPP变形监测性能。为了充分利用多频冗余观测数据,详细研究了每个频点的差分码偏差(DCB)和全球定位系统(GPS)存在的相位频率间卫星钟偏差(PIFCB)的改正方法,扩展了多频数据处理的严密理论模型,能够灵活处理GPS三频、Galileo五频和BDS-3五频观测数据。多频PPP振动监测实验结果表明,GPS三频PPP、BDS-3五频PPP、Galileo五频PPP较各自双频PPP位移监测精度可分别提升12%、13%和14%,表明多频PPP技术有利于提升PPP位移监测精度与稳定性。

Precise Point Positioning(PPP)technology is expected to solve the problem that it is difficult to find a stable reference point in long-distance and large-scale monitoring scenarios.With the development of Global Navigation Satellite System(GNSS),there is an emerging situation that the new-generation GNSS satellites are operating with multiple frequencies.Theoretically,the multi-frequency integration can improve the performance of deformation monitoring with PPP.In order to make full use of the multi-frequency redundant observation data,the correction method of the Differential Code Bias(DCB)of each frequency and the Phase Inter-Frequency Clock Bias(PIFCB)existing in GPS is studied in detail.The correction method extends the rigorous theoretical model of multi-frequency data processing,which can flexibly process GPS triple-frequency,Galileo five-frequency and BDS-3 five-frequency observation data.The results of the multi-frequency PPP vibration monitoring experiment show that the vibration displacement accuracy of GPS triple-frequency PPP,BDS-3 five-frequency PPP and Galileo five-frequency PPP can be improved by 12%,13%and 14%,respectively,compared with their dual-frequency PPP.Thus,the multi-frequency integration is beneficial to improve the accuracy and stability of PPP displacement monitoring.