Analysis of cooperative MIMO transmission system with transmit antenna selection and selection combining

Error performance of a cooperative system can be enhanced by using transmit and receive diversity techniques at transmission links. The number of transmit/receive RF chain pairs required to achieve full diversity can be decreased to one for each link by using transmit antenna selection (TAS) method at the transmitter and selection combining (SC) method at the receiver. Thus, hardware complexity of a multiple input multiple output (MIMO) cooperative scheme can be significantly reduced when compared to systems that use TAS and maximum ratio combining (MRC). In this paper, we investigate the performance of an amplify-and-forward cooperative system where TAS/SC is utilized. We derive the probability density function (pdf) of end-to-end SNR of the system for Rayleigh fading channels. By using this pdf, we obtain the exact symbol error rate expressions for M-PSK and M-QAM modulations and the exact outage probability expression. We also obtain the asymptotical diversity order using upper and lower bounds of the outage probability expression and show that our system provides the same diversity order as the cooperative system where TAS/MRC is utilized. We verify our results via computer simulations.