线性化误差对于UWB系统定位精度影响分析

针对目前常用的超宽带算法,扩展卡尔曼滤波(EK F)在解算过程中产生的线性化误差,对定位结果产生影响,而无损卡尔曼滤波(UKF)算法可以不进行线性化过程进行解算,避免误差的产生.文中首先对UWB定位系统线性化误差进行分析,在此基础上提出UKF和TDOA相结合的定位模型,通过实验比较两种算法的定位精度.实验结果表明U K...

Influence of linearization error on positioning accuracy of UWB system

In view of the commonly used UWB algorithm,EKF will produce linearization error in the process of solution,which has an impact on the positioning results,while UKF algorithm can avoid the linearization process to solve the error.In this paper,firstly,the linearization error of UWB positioning system is analyzed.On this basis,a positioning model combining UKF and TDOA is proposed,and the positioning accuracy of the two algorithms is compared through experiments.The experimental result shows that compared with EKF algorithm,UKF algorithm has a significant improvement in U direction,and the error is stable within 10 cm.At the same time,by changing the initial coordinate deviation to further compare the positioning effect of the two algorithms,the result shows that when the initial deviation is set to 0.5 m,the UKF algorithm improves the u-direction accuracy by 15%compared with the EKF algorithm;when the initial deviation is set to 1m,the UKF algorithm improves the u-direction accuracy by more than 60%;when the initial deviation is set to 5 m and 10 m,the UKF algorithm improves the u-direction accuracy by 90%.To sum up,EKF algorithm will produce non negligible linearization error and the error will increase with the increase of initial deviation.UKF algorithm can maintain good positioning accuracy and stability.