在陆地导航系统中使用GNSS/INS组合导航会增加系统成本,多天线GNSS测姿精度受基线长度影响,且存在的模糊度固定问题。本文提出仅利用一个陀螺仪和单天线GNSS组合来进行实时测姿。先由单天线GNSS计算姿态角3参数,航向角为陆地导航的关键参数,为此将陀螺信息与GNSS导出的航向角进行融合。分析了单天线测姿在载体静止或低速运动时精度很差的原因,提出了在组合滤波中进行解决的方案。推导了GNSS和陀螺信息融合的滤波模型,将陀螺仪信息作为状态模型的控制输入,以GNSS航向为滤波观测值。实验结果表明,GNSS/陀螺仪组合计算的航向角精度和可靠性相对GNSS测姿结果均有很大提升。
It is wasteful to use a GNSS/INS integrated system for land navigation. Multi-antenna GNSS attitude determination is closely related to the baseline length and is confronted with the ambi- guity fixing problem. This paper proposes a single-antenna GNSS /gyroscope integrated attitude de- termination method that meets this challenge. The three attitude parameters are firstly calculated by single-antenna GNSS and then the key parameter in land navigation, the heading angle, the gyro in- formation, and GNSS-derived heading are integrated. The accuracy degration problem in single-anten- na GNSS during the stationary or low-velocity conditions is investigated and solved during the integra- tion filtering process. The filtering model for GNSS/Gyro integration is derived~ gyro information is used as the control input in the state model and the GNSS heading angle is measured. Experimental results show that, the accuracy and reliability of the GNSS/Gyro heading is much higher using the proposed method than that of GNSS attitude determination alone.