GPS/BDS/GLONASS双频RTK定位算法研究

针对GLONASS采用频分多址技术导致双差观测方程中双差模糊度失去整周特性的问题，提出了一种基于站间单差模糊度分别求解的方法，并结合附加模糊度参数的卡尔曼滤波模型，实现了GPS/BDS/GLONASS组合RTK定位。通过自编RTK程序对GPS、BDS与GLONASS双频实测短基线数据进行测试，并对比分析其他RTK模式下的稳定性与定位精度。结果表明，GLONASS单频和双频定位的模糊度固定率分别为99.8%、99.7%，其定位精度与BDS、GPS相差不大。在单频或双频RTK定位中，双系统、三系统组合定位的稳定性和定位精度明显高于单系统，其中三系统组合定位的稳定性最好，精度最高。随着频率增加，初始化时间明显减少，为实现单历元获得固定解提供了可能性。

Research on GPS/BDS/GLONASS dual-frequency RTK positioning algorithm

In the double difference observation equation, the double difference ambiguity loses the whole circumference characteristics for using FDMA technology for GLONASS. To solve it, this paper proposes a method based on the interstation single difference ambiguity, and additional ambiguity parameters Kalman filter, it implements GPS/BDS/GLONASS combined RTK positioning. The RTK program is used to solve measured short baseline data of the GPS, BDS and GLONASS dual-frequency, and the stability and positioning accuracy in other RTK modes are compared and analyzed. The results show that the fixed rate of ambiguity of GLONASS single frequency and dual frequency positioning is 99.8% and 99.7%, respectively, and its positioning accuracy is not much different from BDS and GPS. In single-frequency or dual-frequency RTK positioning, the stability and positioning accuracy of the dual-system and three-system combined positioning are significantly higher than that of the single system. The stability of the three-system combined positioning is the best and the highest precision. As the frequency increases, the initialization time is significantly reduced, providing the possibility to achieve a fixed solution for a single epoch.