基于冗余GNSS观测的RTK/INS紧组合方法

The tightly coupled RTK/INS integration method based on redundant GNSS measurement

关键词:  冗余GNSS观测；组合导航；RTK/INS  紧组合；模糊度固定

Key words:  Redundant GNSS measurement  Integrated navigation  RTK/INS  Tight integration  Ambiguity resolution

摘要:

为了解决传统全球卫星导航系统(GNSS)与惯性导航系统(INS)的紧组合方法在隧道、高架等复杂场景下定位精度退化、相位模糊度固定率低的问题，提出了一种基于冗余GNSS观测的RTK/INS紧组合方法，可以紧密集成任意个GNSS终端，通过大量的冗余观测与改进卫星几何构型，有效提高了系统的定位性能。实验验证与定量分析表明，该方法在城市环境中能够稳定实现厘米级的精度，在卫星数急剧减少的复杂场景下与单天线紧组合方法相比，显著改善了定位效果，将最大误差由接近3 m约束到了1 m以内，并将模糊度固定率提高了20%。

Abstract:

To address the degradation of positioning accuracy and low ambiguity fix rate in complex scenarios such as tunnels and overpasses using the traditional tight integration between global navigation satellite system (GNSS) and inertial navigation system (INS), a tightly coupled RTK/INS integration method based on redundant GNSS observations is presented. This method can seamlessly integrate any number of GNSS terminals and effectively improve the positioning performance of the system through improved satellite geometry configuration and abundant redundant observations. Experimental verification and quantitative analysis show that this method can achieve centimeter-level accuracy in urban environments and significantly improve positioning performance compared to single-antenna tight integration methods in complex scenarios with a drastic reduction in the number of satellites. The maximum error is limited to 1 m, compared to nearly 3 m, and the ambiguity resolution rate is increased by 20%.