北斗双频组合动对动高精度相对定位新算法

针对动对动相对定位基线矢量实时变化导致整周模糊度浮点解在动态情况下难以快速精确求解的问题,提出了一种北斗双频动对动相对定位算法:对组合双差方程基线向量的系数矩阵进行奇异值分解,并变换组合双差方程以消除基线参量,将变参数估计问题转化为定参数估计问题,然后采用递推最小二乘算法实时推算组合模糊度的浮点解及其协方差矩阵,在此基础上,采用最小二乘模糊度降相关平差法(LAMBDA)搜索和固定组合模糊度。试验结果表明,该方法能够快速准确固定组合模糊度,与单频解算相比,初始化时间用时更短,基线误差在5 cm以内,能较好地适用于动对动相对定位。

New method for Beidou dual-frequency kinematic-to-kinematic relative positioning

In kinematic-to-kinematic relative positioning,the floating solution of the integer ambiguity is hard to quickly and accurately be solved in dynamic situations due to the baseline vector's real-time change.To solve this problem,a novel algorithm is proposed for Beidou dual-frequency kinematic-to-kinematic relative positioning.Firstly,the coefficient matrix of the baseline vectors of combined double-differential equations are decomposed by singular value decomposition,and the combined double-differential equations are transformed to eliminate the baseline parameters,so that the variable-parameter estimation problem is transformed into the constant-parameter estimation problem.Then,the floating solution and the covariance matrix of combined double-differential integer ambiguities are deduced in real-time by Recursive Least Square method.Based on this,the combined integer ambiguities are searched and fixed by LAMBDA algorithm.Experiment results show that,compared to single-frequency solution method,the proposed method takes less time,and the baseline error is within 5 cm,showing that it is suitable for applying in high-precision kinematic-to-kinematic relative positioning.