复杂城市环境多模RTK/SINS紧组合定位性能分析

Performance analysis of multi-mode GNSS RTK/SINS tight combined positioning in complex urban environment

利用全球卫星导航系统(GNSS)实时动态差分(RTK)与捷联惯导系统(SINS)进行紧组合定位,是解决高精度GNSS导航定位技术在复杂城市环境中性能受限问题的有效途径之一。为深入分析紧组合方案的定位性能,将开阔环境的RTK/SINS紧组合定位结果当作参考值,对典型复杂城市环境进行了分类和掩模,并在仿真环境中,评估分析了全球定位系统(GPS)与北斗卫星导航系统(BDS)双星座组合定位,GPS/BDS/GLONASS(格洛纳斯卫星导航系统)三星座组合定位、GPS/BDS/GLONASS/QZSS(日本准天顶卫星系统)四星座组合定位,以及单RTK、RTK/SINS紧组合等不同融合策略下的定位性能。实验结果表明,在各类复杂城市仿真环境中,不同星座组合的RTK/SINS组合定位性能,较RTK定位性能有较大提升,其中四星座组合定位性能最优。在单一的掩模仿真城市环境中,紧组合模糊度固定率和车道级定位可用率分别能达70%、90%以上,定位精度通常优于15 cm;而在掩模仿真组合复杂城市环境条件下,紧组合模糊度固定率和车道级定位可用率为64%、82%左右,定位精度约为40 cm。

The use of Global Navigation Satellite System(GNSS) Real-Time Kinematic(RTK) technology and Strapdown Inertial Navigation System(SINS) tightly coupled positioning solution is one of the effective ways to solve the problem of highprecision GNSS navigation and positioning technology in complex urban environments. In order to deeply analyze the positioning performance of the tight combination scheme, the RTK/SINS tightly coupled positioning result in the open environment is used as a reference value, and the typical complex urban environment is classified and masked. In the simulation environment, different constellations, namely Global Positioning System(GPS) and BeiDou navigation satellite System(BDS), GPS/BDS/GLONASS(GLObal Navigation Satellite System), GPS/BDS/GLONASS/QZSS(Quasi-Zenith Satellite System) and different fusion strategies(single RTK, RTK/SINS tightly coupled) positioning performance. Experimental results show that in various complex urban simulation environments, RTK/SINS with different constellations have a greater improvement in positioning performance than R T K, and the four constellations are opt imal. In single mask simulation urban environments, the tightly coupled ambiguity fixed rate and lane-level positioning availability rate can reach 70% and 90%, respectively, the positioning accuracy is usually better than 15 cm;while in the mask simulation combination complex urban environment, the tightly coupled ambiguity fixed rate and lane-level positioning availability rate is about 64% and 82%, and the positioning accuracy is about 40 cm.