GPS信号变化对北斗地基增强系统数据的影响分析

The impact of GPS signal change on Beidou-ground augmentation system

为了研究GPS信号变化对北斗地基增强系统基准站的影响,本文选取北斗地基增强系统全国均匀分布18个基准站2018年4月10号到4月16号的观测数据,从多路径效应与观测噪声、周跳比等方面进行了数据质量分析。研究结果表明,GPS L2频点的S2P信噪比在4月12号到14号有4~5dB的增幅,L1频点、L5频点无明显变化;GPS L2频点的变化未造成BDS和GLONASS有明显失锁现象;BDS三频多路径误差与观测噪声的RMS平均值分别为0.2米、0.25米、0.2米,GPS三频多路径误差与观测噪声的RMS平均值分别为0.3米、0.4米、0.35米,GLONASS双频多路径误差与观测噪声的RMS平均值分别为0.26米、0.25米;GPS L2P频点发生变化后的GPS单系统定位结果在收敛后E/N/U方向误差均能达到分米级。

The data quality analysis of multipath and cycle-slip,etc are conducted by using of 18 stations,7 days’observing data based on BeiDou Ground-based Augmentation System.The research results show that the signal-to-noise ratio of GPS L2P frequency has 4~5 dB increase from April 12th to 14th,and there is no obvious increase in L1 frequency and L5 frequency;the change of GPS L2P frequency does not cause BDS and GLONASS to have obvious lock-up phenomenon;the RMS average of BDS tri-band multipath error and observed noise are 0.2 m,0.25 m,and 0.2 m,respectively,and the RMS average of GPS tri-band multipath error and observed noise are 0.3 m,0.4 m and 0.35 m,the RMS average of GLONASS dual-frequency multipath error and observed noise is 0.26 m and 0.25 m,respectively.After GPS L2P frequency change,the GPS single system PPP result of the E/N/U direction error after convergence can reach decimeter.