Research On Key Technologies Of Vehicle Cluster Cooperative Positioning

Since the commercial implementation of the 5th-Generation Mobile Communication Technology(5G)has made the application scenarios of the wireless positioning system more extensive,the demand for wireless positioning system has been increasing significantly.As the positioning scenarios are becoming increasingly complex,it is a key problem that how to achieve the required positioning in various complex scenarios which needs to be solved urgently in many fields.Modern location services are developing rapidly towards the direction of large coverage,full time,high real-time,high precision and strong robustness.Bei Dou Navigation Satellite System(BDS)and Global Positioning System(GPS)have solved most of the positioning and navigation problems in outdoor scenarios.However,the satellite signals are rapidly attenuated or even completely blocked in complex scenarios such as urban canyons,making it difficult to provide high-performance and sustainable positioning services.In order to compensate for the lack of positioning accuracy of satellite positioning technology in complex scenarios,this thesis studies two schemes to provide positioning services for single base station scenario and cooperative positioning scenario respectively.The specific researches and contributions of this thesis are as follows:(1)This thesis studies the wireless ranging principle based on double two way ranging and the wireless angle measuring principle of the multidimensional scaling algorithm.The advantages and disadvantages of wireless positioning information observation methods such as time of arrival,time difference of arrival,received signal strength and angle of arrival are compared.It lays the foundation for the following research on the key technologies of single base station positioning and cooperative positioning.(2)In view of the reduction of positioning accuracy caused by serious multipath effects,this thesis studies a single base station positioning algorithm.Specifically,this algorithm uses Orthogonal Frequency Division Multiplexing several specific sub-carriers to range simultaneously.And it uses the uniform circular antenna array based on time division multiplexing to measure the array direction vector.The algorithm not only has little impact on communication capacity,but also saves spectrum resources and reduces power consumption.Simulation experiments show the effectiveness and accuracy of the algorithm.(3)In view of the problem of low anchor nodes positioning accuracy in vehicle cluster cooperative positioning,this thesis studies a cooperative positioning algorithm.Firstly,the Multidimensional Scaling-MAP algorithm is used to correct the BDS/GPS position of the anchor nodes.Then,the least square algorithm is used to calculate and estimate the position of the target vehicle.The actual test shows that the algorithm greatly reduces the final positioning error caused by the inaccurate positioning of the anchors.Compared with the positioning algorithm without anchor nodes correction,the accuracy of the proposed algorithm is improved by 25%.This verifies the effectiveness and practicality of the proposed algorithm.After studying the latest progress of vehicle positioning,this thesis studies a single base station positioning algorithm and a vehicle cluster cooperative positioning algorithm for two problems of low ranging accuracy and large anchor node positioning error.The accuracy and effectiveness of the proposed positioning algorithms are verified by experiments.