Relay Selection for Dual-User Amplify-and-Forward Systems in a Dense Relay Environment

We investigate a dual-user scenario where sources transmit their messages to the destinations by means of relays in an amplify-and-forward two-hop mechanism. In this scenario, the presence of co-channel interference requires the design of a suitable relay selection algorithm to minimize outage events. To this aim, we present a relay selection algorithm specifically tailored for amplify-and-forward relaying. The performance of the relay selection mechanism is evaluated analytically, in terms of outage probability, under the assumption that relay nodes are distributed according to a homogeneous Poisson point process. Numerical results show that the proposed algorithm outperforms a conventional one, based only on the measurement of the power received from the desired transmitters.