MIMO Coordinated Interference Alignment Techniques Research

For most multiple-input multiple-output(MIMO)wireless communication networks,interference is one of the fundamental factors that restrict the rate of information transmission.As users demand for data services continue to grow and the increasing density of base station distribution,the interference problem,especially the cell-edge interference problem becomes tricky.Interference alignment(IA)as an emerging interference management technique gains high performance in interference networks,and coordinated multi-point(Co MP)transmission technique also exhibits excellent performance while dealing with cell-edge interference.For this and other reasons,IA and cooperative communication techniques in wireless networks arouse the concern of researchers.This paper proposes a concrete solution to investigate the system performance by combining IA technique with Co MP transmission technique,and explores the feasibility of IA in MIMO interference broadcast channel(MIMO-IBC).Firstly,this paper introduces the classification and core principle of cooperative communication technology.The basic principle of IA is also introduced by the concept of degrees of freedom(Do F)and a toy example.Second,this paper presents a concrete CoMP transmission solution that was applied to the original channel to get a derived channel.In this solution,the coordinated set composed of multiple BSs is defined to transmit messages to all users of the same cell,the original channel is divided into two subsystems according to the distribution of the coordinated set,and then the zero-forcing matrix is designed for each coordinated set to eliminate some interference.Then,the article designs an IA scheme in the derived channel.The core idea is to align the interference signals from multiple transmitters into the lower-dimensional signal sub-space at each receiver,and design the transmit beamforming matrix and receive beamforming matrix according to the classical IA conditions.The optimal Do F of the IA scheme based on Co MP transmission is obtained by MATLAB.The performance of the solution is given by the simulation program.Finally,this paper investigates the feasibility of IA scheme for the partially connected networks.The main research method is to establish the relationship between the feasibility of IA scheme and the solvability of multivariate polynomial systems corresponding to IA.