Research On The Capacity Of MIMO Wireless Network Based On Random Geometry

As more and more mobile terminals access the network,modeling and network capacity of wireless networks become the focus and challenge of wireless networks research.The demanding of transmission rate and quality of service is increasing higher.Traditional modeling of wireless networks requires extremely complex system-level simulations to verify.However,with the development of heterogeneous networks,the nodes in the network are more random and more densely distributed,which greatly increases the complexity of system-level simulation.Multi-Input and Multiple-Output(MIMO)technology provides the theoretical foundation and wide application of high-speed data transmission rate for the rapid development of wireless networks.Models of stochastic geometry have been shown to simplify the modeling and analysis of wireless networks while ensuring the accuracy of the network models,which makes up the deficiency of the traditional system-level simulation.Therefore,it is of great theoretical significance and research value to choose to use stochastic geometry model to model and analyze wireless networks.Based on this background,the stochastic geometry theory is be used to model MIMO wireless networks and the network capacity is deeply analyzed in this paper.The specific research contents are as follows:(1)We use Poisson Cluster Process(PCP)of stochastic geometry theory to model a two-tier cellular network,in which the Macro base station is the cluster center,and its distribution is stable Poisson Point Process(PPP).Micro base station is the cluster member whose distribution is non-homogeneous Poisson Point Process Gaussian distribution around the cluster center.Furthermore,the distribution of the mobile users in the network is a homogeneous Poisson Point Process(HPPP),which is independent of the distribution of base station.For downlink,the gains of the direct link and the interference link obey different gamma distributions,respectively.And for uplink,the paper add the shadow from the logarithmic normal distribution,with the derivation of the coverage probability,average spectral efficiency and transmission capacity of the network.Furthermore,the coverage probability and signal-to-interference-and-noise ratio(SINR)threshold value,the density of network node,average spectral efficiency and SINR threshold value,the relationship between transmission capacity and SINR threshold value are given respectively in the simulation,which verify the accuracy of the simulation.(2)We use Hard Core Point Process(HCPP)to model MIMO Ad Hoc networks.Based on this model,we choose slot ALOHA protocol as media access control(MAC)protocol,and adopt spatial multiplexing technology of Multi-Input and Multiple-Output.The fading of the channel is Rayleigh,that is,the gain of direct power and interference power is exponential distribution.What's more,we consider two different transmission models,which are fixed transmission distance and random transmission distance.In addition,the expressions of outage probability(OP)and multi-stream transmission capacity(TC)of MIMO Ad Hoc under two different transmission models are given for the first time.The paper verifies the correctness of the expression about the outage probability and multi-stream transmission capacity given in the Matlab simulation process.