GPS/GLONASS组合精密单点定位研究

Study on Precise Point Positioning Based on Combined GPS and GLONASS

讨论了GPS／GLONAsS组合精密单点定位的数学模型，并以IRKJ跟踪站的观测数据为例，分别利用GPS和GPS／GLONASS组合两种方式进行精密单点定位解算。计算结果表明，当GPS观测卫星数较多（9～10颗）时，组合GPS／GLONASS较单系统GPS的精密单点定位精度及收敛速度有一定改善，但效果不明显。当GPS卫星数较少（4～5颗）时，引入GLONASS卫星进行GPS／GLONASS组合精密单点定位，其定位精度及收敛速度较单系统GPS精密单点均有显著改善。

A combined PPP（Precise Point Positioning） mode is implemented using GPS and GLONASS observations. The performance of the combined GPS and GLONASS PPP was assessed using observations from one of the IGS tracking network （IRKJ） and the currently available precise orbit and clock products. The corresponding positioning accuracy and convergence time were compared between GPS-only and GPS/GLONASS combined precise point positioning. The results show that GLONASS has caused a slight impact on positioning accuracy and convergence time in case of more than 8-9 GPS satellites are tracked. However, when the number of available GPS satellites is not enough, especially is less than 4 - 5, adding a couple of GLONASS satellites can improve positioning accuracy and shorten convergence time significantly.