一种地面连续运行参考站实时质量控制算法

Real-time quality control algorithm for ground continuously operation reference stations

提出了一种适用于地面连续运行参考站(CORS)的实时数据质量控制算法,该算法充分利用地面连续运行参考站GPS卫星精密单点定位得到的载波相位观测量的验后相位残差时间序列,对监测站的多路径误差进行建模。通过设置一定高度角和水平角大小的格网,计算落入相应格网的载波相位观测量验后残差的均值与标准差,将所得均值与标准差作为地面连续运行参考站的载波相位观测量在该方向的多路径误差,并给出了其具体计算步骤。通过10个IGS监测站的实测数据仿真计算表明,该算法能够显著修正载波相位观测量中的多路径误差,当格网设为0.5°×0.5°时,经过多路径误差改正后的相位观测量残差的精度提高了大约30%。最后采用抗差估计,利用载波相位观测量验后残差格网的均值与标准差,对实时精密单点定位(PPP)的载波相位观测量进行质量控制。实测数据表明,在监测站数据存在粗差时,能够显著提高实时PPP的精度,大约提高39.7%。

A real-time data quality control algorithm suitable for ground continuously operation reference stations（ CORS） is proposed.The post-fit phase residual time series of the carrier phase observation value obtained from GPS precise point positioning（ PPP） of CORS are fully utilized in this algorithm. The multipath errors of CORS are modelled with the post-fit phase residual series. The grid with a certain size of elevation angle and horizontal angle is set,the mean and standard deviation of the post-fit phase residuals of the carrier phase observation value that fall into corresponding grid are calculated,which are taken as the multipath errors of the carrier phase observation value of CORS in this direction. The detailed operation steps are presented in this paper. The real data simulation result of10 IGS stations shows that this algorithm can significantly revise the multipath error of carrier phase observation value. When the size of the grid is 0. 5° × 0. 5°,the accuracy of the post-fit phase residual is improved by about 30 percent after correcting the multipath errors.Finally the robust estimation method is adopted to implement the quality control of the real-time PPP carrier phase observation value with the mean and standard deviation of the post-fit phase residual grid of the carrier phase observation value. The test IGS data show that the proposed algorithm can significantly improve the accuracy of real-time PPP,the improvement is about 39. 7 percent when the CORS data have gross errors.