Study On The Performance Of MIMO MRC Cooperative Wireless Communication Systems

Multiple-input multiple-output (MIMO) maximal ratio combining (MRC) technique which has best performance in fading channels compared with other antenna diversity technique, can effectively combat the adverse impact of multipath fading on the performance of wireless communication systems. The application of MIMO MRC technique in cooperative communication system can further improve the anti-multipath fading ability and coverage of the wireless communication system. Unlike amplify-and-forward(AF) relay protocol, decode-and-forward(DF) relay protocol doesn’t require expensive radio frequency(RF) transceivers due to its digital processing nature. In the multi-user environment, relay selection can significantly enhance the transmission reliability of the wireless communication system as well as reduce its implement complexity. In practice, both of the transmitter and receiver can’t obtain the perfect channel state information(CSI) because of the effect of channel fading, noise, etc.. Besides, the received signal in cellular wireless communication systems can be affected by the cochannel interference(CCI) caused by frequency reuse. Therefore, this paper investigates the outage probability and error performance of MIMO MRC antenna diversity system, MIMO MRC single relay cooperative communication system and MIMO MRC relay selection cooperative communication system with perfect/imperfect CSI and/or CCI in the flat Rayleigh fading channel.Chapter1presents a brief review of MIMO MRC antenna diversity technique and cooperative wireless communication technique.Chapter2investigates the error performance of MIMO MRC system, and derives exact/approximate closed-form expressions for the average symbol error rate(SER)or bit error rate(BER) performance of M-ary orthogonal/biorthogonal signals with perfect CSI, M-ary differential phase-shift keying(MDPSK), equiprobable correlated binary signals, π/4-differential quaternary phase-shift keying (DQPSK) with imperfect CSI and rectangular M-ary quadrature amplitude modulation (MQAM) with imperfect CSI and CCI. Numerical and simulation results show that the obtained approximate closed-form expressions have high reliability; channel estimation error can deteriorate the average error performance of MIMO MRC system; when the sum of receiver/transmitter antennas is fixed, MIMO MRC system with evenly distributed receiver/transmitter antennas has best average error performance but is more sensitive to channel estimation error; when the product of receiver/transmitter antennas is fixed, MIMO MRC system with bigger total number of receiver/transmitter antennas provides better performance.Chapter3derives exact closed-form expressions for the average SER of MIMO MRC single relay cooperative communication systems for M-ary phase-shift keying(MPSK), equiprobable correlated binary signals, π/4-DQPSK and rectangular MQAM. The outcome illustrates that the approximate and exact results approach closely, and the average SER performance of MIMO MRC single relay cooperative communication system is better than MIMO MRC system with no relay.Chapter4obtains exact closed-form expressions for the outage probability as well as the average SER performance of the MIMO MRC dual-hop relaying systems and MIMO MRC relay selection cooperative communication system using MPSK, equiprobable correlated binary signals, π/4-DQPSK and rectangular MQAM modulation schemes. Simulation results verify the accuracy of theoretical analysis. Numerical and simulation results also indicate that the outage probability and the average SER performance of the MIMO MRC relay selection cooperative communication system is better than MIMO MRC dual-hop relaying systems, and the performance of the MIMO MRC dual-hop relaying systems and relay selection cooperative communication systems can be upgraded significantly by increasing the antenna number of source nodes, relay nodes and destination nodes.Chapter5finishes the dissertation with concluding remarks.