Performance analysis of energy efficiency and symbol error rate in amplify-and-forward cooperative MIMO networks

In this paper, we analyze the energy efficiency and the symbol error rate (SER) in the cooperative multiple-input multiple-output (MIMO) relay networks. We employ an amplify-and-forward (AF) relay scheme, where a relay access point occupied with Q antennas cooperatively forwards packets to the destination. Under the assumption of Rayleigh fading channels and time division multiplexing (TDM), we derive new exact closed-form expressions for the the outage probability, SER and the energy efficiency valid for Q antennas. Further asymptotic analysis is done in high SNR regime to characterize the energy efficiency in terms of the diversity order and the array gain. Subsequently, our expressions are quantitatively compared with Monte Carlo simulations. Numerical results are provided to validate the exact and the asymptotic expressions. The results show that the energy efficiency decreases with the number of antennas at the relay according to Q+1. The behavior of the energy efficiency with the relay locations is also discussed in this paper.