Research On Spatial Layout-Aided Outdoor Single Station-Based Localization Technology

5G communication technology leads the era of the Internet of Things,and the demand of localization for people is continuously getting higher.Outdoor localization system based cellular network always received the attention of scholars because of its own advantages.Single-station localization system is favored by researchers because it is more convenient and low-cost.At present,most of the cellular network-based localization techniques are processed by extracting signal parameters of mobile terminals.For outdoor single-station localization system,the main dilemma is which direct signal cannot be used for positioning in Non-Line-of-Sight(NLOS)environment.The general localization method in NLOS environment is to utilize multiple base stations to cooperate.However,the clock synchronization between base stations and the signal testability with multiple base stations must be considered.Another method is to detect and suppress the NLOS error and restore the direct signal.But it is difficult to suppress NLOS error directly.In this thesis,outdoor single-station localization is realized by using rich multipath signals in complex environment and combining with scattering model.Firstly,the Angle of Arrival(AOA)and Time of Arrival(TOA)of the signal are estimated by using a two-dimensional smoothing Multiple Signal Classification(MUSIC)algorithm.Aiming at the discrimination of Line-of-Sight(LOS)environment and NLOS environment,the Affinity Propagation clustering algorithm is used to cluster the extracted parameters,then distinguish the localization environment type by calculating weight.Aiming at the localization in NLOS environment,the outdoor single station localization technology based on Particle Swarm Optimization(PSO)optimized Least Squares Support Vector Machines(LSSVM)is used.The effectiveness of the localization algorithm is verified by simulation.Secondly,in order to solve the problem of excessive workload of sample collection in localization scheme based on PSO-LSSVM,an outdoor single station localization technology assisted by spatial layout is designed.Firstly,the scattering area model is constructed according to the spatial layout near the base station,the scattering area model assisted by spatial layout could make up for the lack of information in outdoor single station localization technology in NLOS environment.Then a Fusion Clustering Algorithm is constructed based on K-means clustering and Means Shift clustering algorithm,and it is used to deal with multipath parameters.Then,the positioning equations are constructed combined with the scattering area model,and it is transformed into a nonlinear optimization problem,which is solved by the Levenberg-Marquardt(L-M),and the location of target is calculated finally.Finally,the simulation is processed by using Matlab and Wireless Insite,and the simulation results verify the feasibility and effectiveness of the proposed algorithm.Compare with the traditional outdoor single station localization scheme,the scheme proposed in this thesis improves the positioning performance of the outdoor single station localization system.