Performance Analysis of Hybrid-ARQ over Full-Duplex Relaying Network Subject to Loop Interference under Nakagami-m Fading Channels

In this paper, the outage performance of hybrid automatic repeat request (hybrid-ARQ) over a full- duplex decode-and-forward relay network is analyzed. Nakagami-m distribution is assumed for fading channels such that the analysis results can be easily extended to other fading distributions. Compared to the conventional half-duplex relay mode, full-duplex relay network enables the relay nodes to receive and transmit data with the same time interval and the same frequency band, which leads to improved spectral efficiency and overcomes the loss of limited resources. Due to the full-duplex operation of the relay node, the transmitted signal from the relay node to the destination node will interfere through echo interference channel with the signal coming from the source node since both transmissions occupy the same frequency band. The expressions for the outage probability of the relay network with two different types of hybrid-ARQ schemes, namely type-I hybrid-ARQ and hybrid-ARQ with chase combining, are derived. It is shown that the existence of the loop interference affect the system performance in several ways.