Generalized Virtual Full-Duplex Relaying Protocol Based on Buffer-Aided Half-Duplex Relay Nodes

In this paper, we propose a novel full-duplex relaying protocol that relies on half-duplex relay nodes with data buffers. The proposed protocol doubles the transmission rate compared to the conventional half-duplex relaying protocol. In the proposed scheme, multiple relay nodes receive a source packet, while a single relay node transmits a buffered packet to the destination node at the same time slot. Specifically, our protocol exploits the multiple source-to-relay (SR) broadcast links rather than the single SR unicast link of the conventional bufferaided full-duplex protocol, and hence provides an additional design degree of freedom. We also derive the theoretical bounds of the outage probability and average packet delay based on the Markov chain model. Our numerical results demonstrate that the proposed full-duplex protocol is capable of attaining a lower outage probability than that of the previous full-duplex max-max relay selection scheme, and the lower outage probability is achieved without imposing any additional cost.