| With the rapid development of information technology,services such as navigation and positioning have become more and more prominent in daily life,and people have higher and higher demands for location-based services.This paper comprehensively considers the cost,power consumption and positioning accuracy of the positioning system,uses the high-precision characteristics of UWB positioning and the advantages of low power consumption and low cost of Bluetooth positioning,combines the two,conducts research on the fusion positioning system,and proposes a fusion positioning system.Positioning algorithm,TWR(Two-Way Ranging)algorithm and fingerprint positioning algorithm are integrated and improved to realize a low-cost,low-power and high-precision positioning system.The main research work of this paper is as follows:(1)Analyze and integrate the positioning algorithm of the indoor positioning system.Firstly,the single-sided two-way ranging(Single-sided TWR,SS-TWR)algorithm and the double-sided two-way ranging(Double-Sided TWR,DS-TWR)algorithm in the TWR algorithm were compared and studied,and the DS-TWR with smaller error was selected.As a ranging algorithm for UWB positioning,then establish a fingerprint positioning algorithm model for Bluetooth positioning,collect Bluetooth signals in the offline phase of fingerprint positioning to build a fingerprint library,use the naive Bayesian algorithm to predict the coordinates of the positioning point in the online phase,and finally propose an improved positioning fusion algorithm.The algorithm combines the DS-TWR algorithm and the fingerprint positioning algorithm to obtain the positioning point,which can effectively improve the accuracy of Bluetooth positioning;in addition,only one UWB base station and multiple low-cost Bluetooth beacons are needed to complete the positioning,effectively reducing the UWB base station.Quantity and cost of deployment.(2)Research and design of indoor fusion positioning system.First introduce the whole indoor positioning system from the overall scheme design,show the overall structure combined with the system frame diagram,and then describe the working methods and design points of each component in the system,including tags,base stations,Bluetooth beacons,servers and client software.Finally,this paper chooses the mobile positioning method to conduct experiments,and tests the positioning accuracy of the system.The experimental data shows that compared with the pure Bluetooth positioning method,the positioning system used in this paper has improved in terms of average error and standard deviation.Therefore,it is proved that the positioning algorithm integrated with UWB and Bluetooth technology can effectively improve the positioning accuracy and stability of the single Bluetooth technology fingerprint positioning algorithm,and this conclusion is still valid in the NLOS environment. |
