Performance analysis of cooperative communications with opportunistic relaying

In this paper we investigate the performance of proactive opportunistic relaying with amplify-and-forward (AF) protocol over independent and non-identically distributed Generalized Gamma fading channels. The Generalized Gamma distribution is very versatile and accurately approximates many of the commonly used channel scenarios for multipath, shadow and composite fading. We show that opportunistic relaying not only reduces the amount of required resources but also maintains the full diversity order. We derive the novel closed-form expressions for the cumulative distribution function (CDF) and the probability density function (PDF) for the opportunistic relaying scheme operating over independent and non-identically distributed Generalized Gamma fading channels. Moreover the average symbol error rate (SER), for several coherent and noncoherent modulations schemes, as well as the ergodic capacity novel closed-form expressions are also derived in terms of the tabulated Meijer´s G function. Simulation results are also shown to verify the analytical results.