Asymptotic performance of amplify-and-forward cooperative diversity networks with the Nth best relay over Rician fading channels

This paper analyzes and derives the asymptotic symbol error rate expression of amplify-and-forward cooperative communications with the Nth best relay over independent and non-identical Rician fading channels. Rician fading takes the line-of-sight effects into account and often exists in microcellular mobile and wireless mesh networks. In practice, the Nth best relay is selected when the best relay is unavailable because of fairness and load balancing issues. Performance analysis reveals that the diversity gain of the Nth best-relay scheme equals RN+2, while the best relay and all-participate schemes achieve the diversity gain of R+1, where R is the number of relays. Simulation and numerical evaluation show the tightness of the asymptotic symbol error rate expression and the accuracy of our theoretical analysis. Copyright (c) 2012 John Wiley & Sons, Ltd.