Outage and Average Rate Performances of Full-Duplex Multiuser AF Relay Systems With Time-Selective Fading

Abstract

The outage and average rate performances are studied for a multiuser amplify-and-forward two-way relay system, where all the users are assumed to be mobile, and the effect of mobility is modeled using a first-order autoregressive process. The absolute and normalized channel-power-based scheduling schemes are adopted when channel state information (CSI) is available at the relay node. In the absence of CSI, we consider the random scheduling scheme, where user pairs are selected randomly. To characterize the residual self-interference (RSI) at the full-duplex relay and user nodes, the fading-channel-based approach is used, and RSI is modeled as a Rician-distributed random variable. Using the Gaussian–Chebyshev approximation, expressions for the outage probability and the average rate are derived for the adopted scheduling schemes, and their performance is compared with the hybrid scheduling scheme assuming independent and nonidentically distributed channels. The analytical results are validated through simulations. This article reveals the impact of key parameters, such as user mobility, channel estimation errors, and RSI, on the performance of the considered full-duplex two-way relaying system.