Performance evaluation of a two-way relay network with energy harvesting and hardware noises

In this paper, we propose a Two-Way Cognitive Relay Network (TWCRN) where the secondary users operate on an underlay mode to access the licensed bands. In the proposed protocols, two secondary sources transmit their data to a relay in the first time slot, and then the relay would forward the received information to both sources in the remaining time. Moreover, the relay is self-powered by harvesting energy from ambient Radio Frequency (RF) signals, using the Time Switching (TS) and the Power Switching (PS) method. This paper concentrates on evaluating the performance of the secondary networks under the impact of hardware impairments and co-channel interference from the primary networks. In particular, based on the secondary transmitters' constraint power, we derive the closed-form expressions of the outage probability and the throughput over Rayleigh fading channels in two cases: TS and PS. We also investigate the energy efficiency issue and the locally optimal position of the relay to maximize the system throughput, which provides much information to install the relay location. Finally, our derivations are verified by Monte Carlo simulation.

Automated summary

This paper proposes a Two-Way Cognitive Relay Network (TWCRN) and evaluates the performance of secondary networks under hardware impairments and co-channel interference from primary networks. The closed-form expressions of outage probability and throughput over Rayleigh fading channels in two cases were derived, and the energy efficiency issue and optimal position of the relay for maximizing system throughput were investigated. The derivations were verified by Monte Carlo simulation.