基于改进RTK算法的铁路导航精密单点定位优化

Optimization of precision single point positioning for railway navigation based on improved RTK algorithm

铁路导航精密单点定位容易受到周跳数据的影响,导致定位结果在水平和垂直方向出现相对偏移,针对该问题提出了基于改进RTK算法的铁路导航精密单点定位优化方法。根据铁路导航精密单点定位原理,采用改进RTK算法构建定位模型,初步获取定位结果。使用双频载波相位测量法探测周跳,剔除野值点,获取预处理后的单点数据。消除一阶电离层延迟,结合模糊度固定技术采集浮点数,获取不同模糊度下的位置坐标。求解载波相位整周模糊度固定问题,实现单点定位优化。分析实验结果可知,该方法在相对偏移时间为6×103s时,垂直误差最大仅为2 m,水平误差为0,说明该方法的定位结果精准。

The precise single point positioning of railway navigation is easily affected by cycle slip data,which leads to relative deviation of positioning results in horizontal and vertical directions.To solve this problem,an optimization method of precise single point positioning of railway navigation based on improved RTK algorithm is proposed.According to the precise single positioning principle of railway navigation,the improved RTK algorithm is used to build the positioning model,and the preliminary positioning results are obtained.Double frequency carrier phase measurement method is used to detect cycle slip and eliminate outliers,obtain single point data after preprocessing.The first order ionospheric delay is eliminated,and the floating-point number is acquired with the fixed ambiguity technology to obtain the position coordinates under different ambiguity.Solve the problem of fixed integer ambiguity of carrier phase,and realize the optimization of single point positioning.The analysis of experimental results shows that the relative migration time of this method is 6×103s,the maximum vertical error is only2 m,and the horizontal error is 0,indicating that the positioning result of this method is accurate.