利用Kalman滤波修正卫星导航差分RTK定位坐标

卫星导航差分RTK(Real Time Kinematic)定位方法的定位精度极易受到载波相位整周模糊度固定算法的影响,在模糊度固定失败的情况下,差分RTK定位将出现大幅偏差.针对该问题,基于Jerk模型提出了一种利用Kalman滤波修正差分RTK定位坐标的方法.在传统Jerk模型基础上,将卫星导航系统输出的载体运动速度信息引入状态空间模型的观测方程.基于扩展状态空间模型,利用Kalman滤波器实时修正载体的位置坐标.半实物仿真表明,所提方法能大幅改善卫星导航差分RTK定位精度.

Adjusting differential GNSS RTK positioning coordinate via Kalman filtering

The positioning accuracy of the differential global navigation satellite system(DGNSS) real time kinematic (RTK) system is extremely influenced by the carrier phase integer ambiguity resolution algorithms.Especially,when the integer ambiguity is failed to be fixed,the positioning deviation is bound to sharply increase.Against this issue,based on the Jerk model,a DGNSS RTK positioning coordinate adjusting algorithm via the Kalman filtering is proposed in this paper.The traditional Jerk model is augmented by adding the velocity information obtained from the GNSS single-point positioning into the observation equations.Based on this augmented state space model,the Kalman filtering is used to real-time adjust the DGNSS RTK positioning coordinate.The hardware-in-the-loop simulation results show that the suggested adjusting algorithm can significantly improve the positioning accuracy of the DGNSS RTK system.