Research On UWB-based Positioning Method And Its Application In Logistics Warehouse

With the development of social economy,the continuous expansion of warehouse scale leads to the increase of the quantity of goods in the warehouse,which brings new challenges to the efficient management of goods in and out of the warehouse,so it is urgent to provide high-precision positioning information for goods in the warehouse.In view of the advantages of UWB technology,such as strong anti multipath ability,strong penetration ability and high positioning accuracy,this paper designs a new warehouse positioning system based on UWB positioning technology.By researching the ranging method and positioning principle based on ultra-wideband technology,it is determined that the warehouse positioning system is studied based on the double-sided two-way ranging method and the arrival time difference positioning principle.The traditional Fang positioning algorithm and Chan positioning algorithm are studied.The traditional positioning algorithm can achieve higher positioning accuracy in a line-of-sight environment with a smaller ranging error.But,in a non-line-of-sight environment,the non-line-of-sight propagation of UWB signals increases the ranging error,and the positioning accuracy of traditional positioning algorithms will decrease significantly.This paper focuses on the problem that non line of sight error will seriously affect the positioning accuracy in the actual warehouse environment,innovatively adopt the Wylie method to solve the problem of LOS / NLOS propagation identification of ranging information,and use the biased Kalman filter algorithm to solve the problem of suppression of non-line-of-sight errors in ranging information.To solve the problem that traditional Chan algorithm and Fang algorithm can't track and locate the target to be measured in the moving state with high precision,this paper uses unscented Kalman filter and square root unscented Kalman filter to track and locate the target to be measured in the moving state.In order to achieve the requirements of visualization and automatic storage of warehouse positioning information,this paper designs a upper computer software system of warehouse positioning experiment system based on Qt development platform,which can realize the functions of real-time display of positioning information,real-time display of motion track,automatic storage of positioning information and query of historical information.In the experimental warehouse positioning system,the biased Kalman filter is used to process the ranging information,and the location experiment is performed using the unscented Kalman filter algorithm and the square root unscented Kalman filter algorithm.Experimental results show that the positioning accuracy of the square root unscented Kalman filter algorithm is better than the unscented Kalman filter algorithm in a non-line-of-sight positioning environment.The positioning method proposed in this paper has higher positioning accuracy than traditional positioning algorithms.