Performance analysis of the full-duplex enabled decode-and-forward two-way relay system

Abstract

Operating the full-duplex (FD) mode in the two-way (TW) relay system has the potential to vastly improve the spectrum utilization owing to the simultaneity of the transmission and reception on the same frequency band. However, the severe self-interference (SI) from the transmitting antenna to the local receiving antenna incurred by the FD mode will cause difficulties for decoding the desired signals. Contrary to the traditional theoretical analysis with perfect SI cancellation (SIC), this paper studies the impact of the residual self-interference (RSI) on the outage performance of the FD enabled decode-and-forward (DF) TW relay system. Exact closed-form outage probability expressions are derived based on the power allocation schemes at the relay node. Both the symmetrical and asymmetrical situations are investigated. Furthermore, the asymptotic outage probabilities are derived when the transmitting powers increase to infinity, and the results demonstrate that the outage probabilities monotonically increase and lastly converge to 1 as the transmitting power exceeds a certain threshold. Finally, simulation results are conducted to verify the accuracy of the theoretical analysis.