Enhancing Relay-based Resource Allocation With Adaptive Amplify-and-Forward Relaying

This study considers the resource allocation problem in relay networks for downlink transmission where base station (BS) communicates with multiple mobile stations (MSs) via relay stations (RSs) operating in either half-duplex (HD) or full-duplex (FD) mode. Relay gain factors for Amplify and Forward (AF) protocol are studied and a new one called adaptive AF (AAF) relaying is proposed. The AAF scheme attempts to equalize the signal-to-noise ratio (SNR) across subcarriers, thus providing increased throughputs and proportional fairness in resource distribution. Simulation results of comparative analysis of the AAF relaying scheme and the two basic relaying protocols namely AF and Decode and Forward (DF) are presented in terms of average system throughput, fairness and percentage of call outage under maximum-sum rate (MSR) resource allocation technique. The results show that the AAF scheme achieves superior performances compared to the other ones.