Performance Analysis of Generalized Selection Combining for Decode-and-Forward Cooperative-Diversity Networks

We consider adaptive decode-and-forward (DF) cooperative-diversity system where a source node communicates with a destination node directly and indirectly (through multiple relays). In this paper, we analyze the system where N multiple relays that have the strongest signal strength at the destination are selected out of M relays and forward their received data from the source node to the destination node. We derive closed-form expressions for the average symbol error probability, the outage probability and the average channel capacity. In particular, closed-form expression for the moment generating function of the SNR at the destination node is determined. Then, we find a closed-form expression for the probability density function (PDF) of the total SNR at the destination. This PDF is used to derive the closed-form expressions of the performance metrics. Simulation results are also given to verify the analytical results.