MIMO Wireless Channel Modeling And Simulation In High-speed Mobile Environment

With the coming of high-speed rail era in the world developed countries, China’s high-speed railway has also made significant developments and achievements. In order to meet the mobile users’needs of high-speed data transmission services in the high-speed mobile environment, Multiple Input Multiple Output (MIMO) technology used in the high-speed railway mobile communication attracts more and more attention. The technology also used in B3G and even the future wireless mobile communication system has broad application prospect and plays a more and more important role. In the high-speed railway communication environment, received signals will be destroyed by the multipath fading because of the fast moving train. So we must establish an accurate, reasonable and effective MIMO dynamic wireless channel model to resist fading influence and improve spectrum efficiency.Compared with the conventional wireless communication system, MIMO wireless communication system takes full advantage of the space propagation characteristics of the signal. It can increase the system’s spectral efficiency and capacity to realize the high-speed date transmission without any increase in bandwidth and antenna total transmission power exponentially.Firstly, the research background and significance is described. Then, the summary of the development of wireless mobile communication and the status of oversea and domestic research and development trends on MIMO channel are introduced.Secondly, based on the throry of large-scale fading and small-scale fading, the characters of radio fading channels are described in detail, and the relevant model is given and analyzed. The MIMO channel modeling methods are classified and two MIMO channel modeling methods, such as deterministic fading channel model and statistical model (empirical model), are introduced. Then the paper briefly describes the MIMO channel model used in the3G and B3G/4G system.Thirdly, based on the3GPP TR25.996SCM and the radio propagation around high-speed railway, this paper proposes a dynamic MIMO scattering wireless channel model under the high-speed railway environment. Then the channel model is built and simulated. The proposed dynamic channel model is used to study and analyze the spatial correlation in the condition of the mobility of the mobile station and the change in the initial distance between receiving effective scatters and receiving antenna phase center. The simulation results show that the spatial correlation increases with increasing time and the initial distance between effective scatters and receiving antenna phase center. The experiment result agrees with the theory analysis which proves the efficiency and validity of the channel model. The result lays the foundation for improving the performance of MIMO mobile communication system.Lastly, in order to further improve the transmission quality of the MIMO mobile communication system under the environment of high-speed railway, an improved and realistic dynamic MIMO scattering wireless channel model is proposed based on3GPP TS36.101. The simulation result shows that the improved channel model can analog the channel characteristics. Then the performance of different receivers is simulated.