Research On Massive MIMO Channel Non-stationary Properties And Channel Modeling

Massive MIMO wireless communication systems,in which the base stations equipped with tens or hundreds of antennas,emerge as a promising technology for the 5G wireless communication networks.In order to evaluate and optimize the performance of massive MIMO wireless communication systems,it is essential to develop accurate,flexible,and efficient channel models which fully reflect characteristics of massive MIMO channels.In this thesis,several extensive models are proposed to capture the specific properties of massice MIMO channels.First,previous literature about the classification of conventional channel models are reviewed.Channel models can be classified into physical models and analytic models based on different modeling approaches,and several standard channel models are briefly introduced.In addition,recent advances on massive MIMO channel measurements are reviewed and the specific properties of massive MIMO channels caused by massive MIMO antenna arrays are analyzed.Second,a novel non-stationary wideband multi-confocal ellipse Two-Dimension(2-D)Geometry-based Stochastic Channel Model(GSCM)for massive MIMO channels is proposed.Taking the near-field effects of massive MIMO into consideration,spherical wavefront is assumed rather than the plane wavefront assumption used in conventional MIMO channel models.In addition,a birth-death process is incorporated into the proposed model to capture the non-stationary properties of clusters on both the array and time axes.Third,we extend the WINNER II channel model with new features to make it as realistic as possible.Three-Dimension(3-D)antenna patterns,3-D propagation and spherical assumption are supported in the proposed channel model,in addition,smooth time evolution of large-scale and small-scale parameters are taking into consideration in which a birth-death process of clusters on the time axe is used to model the transition between segments.Finally,we propose a non-stationary 3-D wideband twin-cluster model for massive MIMO communication systems.Since the dimension of antenna arrays cannot be ignored for massive MIMO,near field effects instead of far field effects are considered in the proposed model.These include the spherical wavefront assumption and a birth-death process to capture the dynamic properties of clusters on both the array and time axes.