GPS/Galileo实时精密单点定位精度分析

在组合PPP函数模型分析的基础上，采用CNES提供的多系统实时轨道和钟差信息，实现GPS/Galileo组合单双频实时静动态PPP，并选取10个MGEX站10 d的观测数据进行解算分析。结果表明，单双频实时静态PPP中，GPS/Galileo组合的定位精度略优于单纯的GPS；单双频实时动态PPP中，GPS/Galileo组合具有较好的定位效果。相较于单纯的GPS，GPS/Galileo组合单频PPP在E、N、U方向平均精度为10.6 cm、9.8 cm、22.5 cm，分别提高了5.4%、4.9%、10.4%；双频PPP在E、N、U方向平均精度为4.3 cm、2.9 cm、7.0 cm，分别提高了6.5%、6.5%、5.4%。同时，GPS/Galileo组合PPP较GPS在收敛时间方面也有一定的改善。

Accuracy Analysis of Real-Time GPS/Galileo Precise Point Positioning

Based on analysis of combined precise point positioning (PPP) model, we investigate single- and dual-frequency real-time static and kinematic GPS and GPS/Galileo precise point positioning, using multi-GNSS real-time orbit and clock products released by Centre National d’Etudes Spatiales (CNES). Through the ten days observations from ten Multi-GNSS experiment (MGEX) stations, the solutions of different PPP models are then obtained. The results show that GPS/Galileo combined PPP outperforms GPS-only. However, while the accuracy of GPS/Galileo combined PPP is slightly better than GPS-only PPP for single- and dual-frequency real-time static modes, it presents a significant improvement for real-time kinematic mode. Compared with GPS-only PPP, the average accuracies of GPS/Galileo combined PPP are notably improved by 5.4%, 4.9% and 10.4%, which are 10.6 cm, 9.8 cm and 22.5 cm in the east, north and up directions, respectively, in the single-frequency kinematic positioning. Furthermore, the accuracies of dual-frequency real-time kinematic GPS/Galileo are about 4.3 cm, 2.9 cm and 7.0 cm in the E, N and U directions, respectively; these results present increases by 6.5%, 6.5% and 5.4% compared with GPS-only PPP. Moreover, the GPS/Galileo combination PPP has a certain improvement over the convergence time of a single GPS system.