两种伪距IFB模型在多系统融合精密单点定位中的性能分析

选取全球52个MGEX测站连续7 d的数据对两种伪距频间偏差（IFB）模型在多系统融合精密单点定位中的性能进行统计分析，第一种IFB模型是对每个GLONASS卫星估计一个IFB参数，第二种模型则是采用频率号的一次线性函数估计IFB参数。结果表明，静态条件下两种伪距IFB模型在E、N、U三个方向上定位精度相当；动态条件下两种模型在E、U方向上精度相当，第二种模型比第一种模型在N方向上定位精度提高21%。相同条件下两种伪距IFB模型的收敛速度相差较小且均能达到指定精度，而第一种伪距IFB模型需要估计更多参数。因此综合考虑定位精度和收敛时间，在进行多系统融合精密单点定位时建议采用第二种模型进行伪距IFB估计。

Performance Analysis of Two Pseudorange IFB Models in Multi-System Combined Precise Point Positioning

We select the data of 52 MGEX stations in the world for 7 consecutive days to statistically analyze the performance of two pseudorange inter-frequency bias (IFB) models in multi-system combined precise point positioning. The first IFB model estimates an IFB parameter for each GLONASS satellite, the second model uses a linear function of the frequency number to estimate the IFB parameter. The results show that the positioning accuracy of the two pseudorange IFB models in the three directions of E,N and U under static condition are equivalent, the accuracy of two models in E and U under dynamic condition are roughly the same. The positioning accuracy of the second model is 21% higher than that of the first model in the N direction. Under the same condition, the convergence speed of the two pseudorange IFB models are not much different and both can reach the specified accuracy. Since the first pseudorange IFB model needs to estimate more parameters and comprehensively consider the positioning accuracy and convergence time, it is recommended to use the second model for pseudorange IFB estimation when performing multi-system combined precise point positioning.