Performance Analysis of Cooperative Fixed-Gain Relaying over Asymmetric Fading Channels

Abstract

In this paper, we investigate the performance of a cooperative relay network over Rayleigh-Rician asymmetric fading channels, where a source transmits signals to a destination with the help of multiple fixed-gain amplify-and-forward (AF) relays. Specifically, we derive the closed-form expression for the moment generating function (MGF) of the output signal-to-noise ratio (SNR), and develop an approximate yet accurate method to evaluate the average symbol error rates (ASERs) of the network with respect to three widely used modulations, namely, M-PAM, M-PSK and M-QAM. Moreover, to gain further insights, we provide the asymptotic ASER expressions at high SNR, and thus obtain both of the diversity order and array gain. Finally, the validity of the analytical results is confirmed through some computer simulations.