Outage Analysis of Cooperative Multi-Path Relay Channels with Virtual Full-Duplex Relaying

In this paper, we study a cooperative multi-path relay channel (MPRC) in which multiple relay terminals assist in the packet transmissions from a source to the corresponding destination opportunistically. Among the relays that successfully decode the source packet, the best one in terms of the instantaneous relay-destination channel is selected to forward the decoded packet to the destination. Meanwhile, the source transmits a new packet and the rest relays attempt to decode this packet. This results in a virtual full-duplex MPRC through which a new source packet can be served in each time slot. However, due to the simultaneous relay transmission and source transmission, inter-relay interference (IRI) exists that affects decoding at the rest relays. Conditioned on whether IRI exists in each time slot, a Markov chain analysis model is proposed to characterize the decoding performance at the relays as well as the end-to-end outage performance of MPRC. Simulation results demonstrate that with proper parameter designs to mitigate the IRI, performance gains are achieved by the proposed virtual full-duplex MPRC over a conventional half-duplex MPRC.