双源车载差分卫星导航定位稳定性分析

Stability Analysis of Vehicular Differential BDS/GPS Satellite Navigation

车载卫星导航系统广泛应用于交通时,采用伪距单点定位就可以满足日常驾驶需要,如需进一步提高导航精度就要利用伪距差分技术进行实时车载导航定位,采用单频三差相位平滑伪距观测值,导航精度在2m以内,可进行车道级导航定位。提出了用单频三差码相组合二次差为标准对三差平滑进行质量控制,以减小周跳和粗差的影响。分析了车载卫星差分导航过程中北斗系统和全球定位系统卫星的可见性,通过在算法中实现北斗和全球定位系统联合解算,以增加车载导航的稳定性。

Vehicular GNSS navigation is widely used in traffic system. Normally, pseudo-range single-point positioning can meet the demand of daily driving. However, the differential GNSS navigation must be used to improve the navigation accuracy further. The navigation accuracy is better than two meters when single-frequency triple-difference phase-smoothing pseudorange is used and the traffic lane can be recognized. Second difference of single-frequency triple-difference code and phase combination is proposed to judge quality of the single-frequency triple-difference phase-smoothing so that cycle slip and gross error can be reduced. The visibility of BDS/GPS satellites is analyzed during vehicular differential navigation as well. The stability of navigation is improved by implementing the combined calculation of BDS/GPS in the algorithm.