Multiuser Pairing in Uplink CoMP MU-MIMO Systems Using Particle Swarm Optimization

Multi-User Multiple Input Multiple Output (MU- MIMO) technique is introduced into 3rd Generation Partnership Project (3GPP) Long-Term Evolution (LTE) to enhance the system capacity and spectrum efficiency. On the other hand, Coordinated Multi-Point transmission and reception (CoMP) technique which can reduce inter-cell interference (ICI) significantly, has been adopted in LTE-Advanced as one of the promising techniques to increase the throughput of the cell edge user. However, some new problems appear with the promotion of MU-MIMO technique in the CoMP scenario. Considering the necessity that an enhanced algorithm should be proposed to fit the CoMP scenario, this paper presents a novel capacity maximization criterion for multiuser pairing strategy based on particle swarm optimization algorithm for CoMP MU-MIMO in uplink LTE-A system. Under this criterion, this paper gives two kinds of receivers which are zero forcing (ZF) equalizer and minimum mean square error (MMSE) equalizer in the frequency-domain. Simulation results show that the proposed PSO strategy achieves nearly the same performance to the exhaustive search (ES) algorithm in terms of capacity performance, but with lower complexity.