GPS/GLONASS精密单点定位加速收敛方法研究

Research on Accelerating Convergence Method of GPS/GLONASS Precise Point Positioning

精密单点定位(PPP)在获得稳态浮点模糊度时需要较长的收敛时间,为此,在采用GPS/GLONASS组合PPP缓解卫星几何变化缓慢造成的收敛时间过长基础上,采用将多路径组合修正值应用到PPP模型中和构建基于多路径修正值加权的随机模型两种方法来减少伪距中的多路径效应和观测噪声影响,以提高浮点模糊估计的准确性,进而提高PPP收敛速度和收敛稳定性。利用全球108个IGS测站的7天数据进行试验,结果表明,组合PPP可以在各系统伪距等权重情况下将收敛时间缩短32%,而基于TEQC多路径组合修正值加权的随机模型可以将收敛周期缩短25%。

Precise point positioning（ PPP） requires a longer convergence time to obtain the steady-state float ambiguities.So,based on the usage of GPS/GLONASS combined PPP to mitigate the problem of excessively slow convergence due to the poor satellite geometry distribution,two methods of applying multi-path combination correction values to PPP model and constructing stochastic models based on multipath combined correction are proposed to reduce the multipath and noise effect. Thereby the PPP convergence speed and stability can be improved. 7-day data sets from 108 globally distributed IGS stations were utilized. The results indicated that GPS/GLONASS PPP can reduce the convergence period by 32% in case of equal-weighted pseudoranges for each system,and the weights derived from TEQC multipath observable can reduce that of PPP by 25%.