Performance analysis in SWIPT-based bidirectional D2D communications in cellular networks

In this paper, a novel traffic-aware cooperative cognitive radio network that can enable device-to-device (D2D) communications in cellular system is proposed and investigated. By providing relay cooperation to cellular transmission, D2D users can realize their own two-way communication in the licensed spectrum. Unlike most existing works, in the proposed network, both wireless-powered D2D users can harvest energy via radio-frequency signals received from basic station (BS) through a hybrid protocol which can adaptively utilize both time-switching and powersplitting techniques. Specifically, D2D users perform decode-and-forward operation to transmit signals, and mobile user (MU) employs a selection combining technique. In addition, the performance of both D2D system and cellular system in the proposed network is evaluated by deriving the expressions of their exact outage probability and throughput. Numerical and simulation results validate correctness of derivations and reveal the influence of various system parameters of the proposed network.