Performance analysis of full‐duplex cellular two‐way relay networks with the Nth worst relay selection under channel estimation error and cochannel interference

Abstract

AbstractThis paper considers a full‐duplex (FD) cellular multiuser two‐way multirelay network, wherein one Na‐antenna base station communicates bidirectionally with M single‐antenna users via L single‐antenna amplify‐and‐forward relays. A practical scenario where cochannel interference (CCI) and channel estimation error (CEE) present in the network is considered for the investigation. Considering the CEE and interferers at the relays, we formulate the Nth worst relay selection scheme, which consists the best relay selection as a special case. With such relay selection strategy, we derive the tight lower bound (LB) expressions for the overall outage probability, average bit error rate, and ergodic sum rate with CEE and CCI under Rayleigh fading. Furthermore, we deduce the asymptotic expressions for the overall outage probability and average bit error rate at high signal‐to‐noise ratio. Based on the asymptotic outage expression, we present some practical cases of interest, from which the impacts of CCI, CEE, and residual self‐interference (RSI) (imposed on the FD nodes) on system diversity order are presented. It is shown via the numerical results that CEE, CCI, and RSI have detrimental impact on the system performance. Our results also reveal that the impacts of CEE, CCI, and RSI can be alleviated by increasing the number of relays. We also obtain some insights on the self‐interference cancelation requirements for the FD mode. The numerical and simulation results verify our theoretical analysis.