采用相位平滑伪距方法研究两种卫星导航系统组合定位的精度

Research on Combined Positioning Accuracy Using Carrier Smoothed Pseudo-range Method

北斗卫星导航系统目前已经开始提供区域定位服务。为了研究北斗系统单点定位精度以及与全球定位系统组合定位效果,采用赫奇滤波方法对全球定位系统单系统、北斗系统单系统以及双系统消电离层组合伪距观测值进行相位平滑,并对单系统以及双系统消电离层组合的定位结果进行比较分析。实验结果表明,平滑后的定位误差更稳定,误差波动范围明显变小。目前北斗系统平面精度10m,高程精度优于20m。因为北斗系统星历精度目前还不及全球定位系统星历精度,在全球定位系统观测卫星足够时,引入北斗系统观测值并不一定能提高定位精度。

BeiDou satellite navigation system(BDS)has been providing regional positioning service.In order to study the point positioning accuracy of BDS and combined BDS/GPS,the method of smoothing the code-code ionosphere-free combination of GPS、 BDS and combined GPS/BDS based on Hatch-type filtering using the phase-phase ionosphere-free combination is used,and the positio- ning results are analyzed comparatively.The conclusionis that the positioning error is more stable and the range of the error fluctuation is smaller when using the carrier smoothed pseudo-range.Currently the horizontal precision of BDS is 10m,and the height precision is better than 20m.And the ephemeris precision of BDS is less than that of GPS,so when the visible satellites of GPS are sufficient,the positioning precision is not significantly improved by adding BDS observations.