Research On Channel Modeling And Handover Algorithm In LTE-R System

As an important research direction of the fifth generation communication technology,the goal of high-speed rail communication is to provide a wireless communication network with high speed,large capacity and high reliability.However,complex wireless environments and ultra-high operating speeds present challenges for existing high-speed rail wireless communication systems.Therefore,for high-speed rail wireless communication systems,accurate high-speed rail channel modeling and excellent handover algorithm design are essential.Based on this,this thesis focuses on the non-stationary MIMO channel modeling and handover algorithm optimization in LTE-R system.The main work is as follows:(1)High-speed rail non-stationary MIMO channel modeling:Based on the analysis of the defects of traditional channel modeling methods,this paper studies and proposes a high-speed rail-based non-stationary MIMO channel model,which introduces channel parameters with time-varying characteristics.Among the MIMO channel models,the non-stationary wireless channel environment in the high-speed rail scene can be more accurately reflected.Finally,the non-stationary characteristics of the high-speed rail channel and the accuracy of the proposed channel model are verified by the derivation and simulation of the statistical parameters of the non-stationary channel.(2)Handover algorithm for parameter prediction and dynamic adjustment:In this paper,based on the single defect of the channel model in the study of handover algorithm,a research method based on speed matching channel model is proposed.The new research method can help the in-depth study of the handover algorithm.In this paper,a high-speed rail adaptive handover algorithm based on dynamic prediction function is proposed.The algorithm can predict and dynamically adjust the handover parameters according to the train speed.Finally,the accuracy of the algorithm to predict the handover parameters is verified by the simulation platform.It is proved that the new handover algorithm can effectively improve the handover success rate of high-speed trains compared with the handover algorithm of fixed handover parameters at different vehicle speeds.(3)LTE-R system-level dynamic simulation platform construction:The performance research of traditional wireless communication algorithms is mostly based on link-level simulation,which cannot fully reflect the overall impact of the algorithm on the communication system.This topic is based on the research of LTE-R high-speed rail communication system.The LTE-R high-speed rail system-level dynamic simulation platform was built(Mainly responsible for building the wireless channel subsystem and mobility management subsystem).The accuracy of the simulation platform was verified by comparing the system-related data indicators with the existing literature indicators.Finally,combined with Matlab's simulation of the proposed channel model and handover algorithm,the simulation results can verify the validity and accuracy of the algorithm more accurately from the system level.In summary,this paper focuses on the LTE-R high-speed rail wireless communication system,focusing on the channel modeling and handover technology in high-speed rail communication.Aiming at the shortcomings of traditional algorithms in research methods and algorithm performance,this paper proposes a new algorithm research method and deeply studies the high-speed rail non-stationary MIMO channel modeling method and dynamic parameter adjustment handover algorithm.Finally,this paper builds a LTE-R high-speed rail system-level dynamic simulation platform to verify the performance of the proposed algorithm.