北斗二代卫星导航系统定位精度分析方法研究

Study on Method of Analyzing the Positioning Accuracy of Beidou 2nd Generation Satellite Navigation System

卫星导航系统的定位精度主要受观测量的精度和卫星的空间几何分布两方面的影响,GPS等相同轨道分布的卫星导航系统一般采用几何精度因子(GDOP)来分析定位精度。我国的北斗二代卫星导航系统是由三类异质卫星组成的混合星座导航系统,不同轨道卫星定轨误差不同,用户所得到的观测量精度也不相同,因此精密定位精度计算和分析时必须要考虑这种差异。引入了加权几何精度因子(WGDOP),利用模拟观测数据对北斗二代卫星导航系统的定位精度进行了分析。外部检核计算结果表明,精密定位计算时顾及观测量精度差异可进一步提高定位精度。

Positioning accuracy of satellite navigation system is subjected to the influence of observation＇ s accuracy and the geometrical configuration. Generally GPS and other similar satellite navigation system using Geometric Dilution of Precision （GDOP） to analyze the positioning accuracy. The beidou 2nd generation satellite navigation system of our country is the mixed constellation navigation system, which is composed of three kinds of satellites. Because the errors of satellites that belong to different categories in different orbits , the observation accuracy of user received is different , so when calculating and analyzing the precise positioning accuracy we must consider this kind of difference. The weighted Geometric Dilution of Precision （WGDOP） is introduced in this paper, Using the simulated observing data, we analyzed the positioning accuracy of the beidou 2nd generation satellite navigation system. The conclusion of exterior checking shows that considering the different observation accuracy when doing precise positioning calculation can further enhance positioning accuracy.