A Study On Non-stationary Characteristic Modeling Of Massive MIMO Wireless Channels

In the rapidly changing information field,mobile communication technology has been fully developed.To meet the constantly increasing demands for higher data rates,Massive MIMO technology,which has dozens or hundreds of antennas at the base station,is one of the potential developing technologies in 5G technology and gradually becomes a hot research topic in wireless communication.By directly increasing the number of base station antennas,Massive MIMO can cause the system to increase the system capacity,spectrum efficiency and energy efficiency without increasing the bandwidth.In this thesis,according to the propagation characteristics of Massive MIMO channel,the elliptical channel model based on the scatterer visible region method,the mixed birth and death process and the scatterable domain method is studied.Firstly,this thesis introduces the development trend of mobile communication and the characteristics of wireless channel propagation.Several common modeling methods are introduced for traditional MIMO channels.The characteristics of the massive MIMO wireless channel,channel measurement and modeling work are summarized.Secondly,three methods are used to simulate the nonstationarity of the scatterer cluster in the array.In the birth and death process,the survival rate and death rate of the scatterer cluster are derived,and the scatterer clusters on the antenna array were simulated.In the cluster visibility region method,it is assumed that the visible range of each antenna is represented by a visible dashed circle.When the distance betwee n the scatterer cluster and the antenna is smaller than the radius of the circle,the scatterer cluster can be observed by a specific antenna.According to the idea of the visible region,the clusters observed by the antenna can be simulated and paired.In the mixed birth and death process and the scatterer visible region method,the birth and death process is used at the transmitter,the visible region is used at the receiver,and the cluster sets of the scatterers on the antenna array can be simulated and paired.The above three methods can capture the non-stationary characteristics of the antenna array dimension.Finally,in this paper,we refer to the traditional MIMO stochastic geometric modeling process,and combine the spherical wave assumption and non-stationary characteristics of the massive MIMO channel.In the massive MIMO confocal elliptical channel model,we use the visible region method modeling channel non-stationary characteristics.When the spherical wave propagation is used,the position information of scatterers,receivers and transmitter antennas is applied to the calculation of channel impulse response.Then the spatial correlation of this model is analyzed.The simulation results show that the spatial correlation results are basically the same as the related literatures.This modeling method captures the characteristics of massive MIMO channels.