Wireless information and power transfer in two-way amplify-and-forward relaying channels

Various wireless networks have made the ambient radio frequency signals around the world. Wireless information and power transfer (WIPT) enables the devices to recycle energy from these ambient radio frequency signals and process information simultaneously. In this paper, we develop a WIPT protocol in two-way amplify-and-forward relaying channels, where two sources exchange information via an energy harvesting relay node. The relay node collects energy from the received signal and uses it as the transmission power to forward the received signal. We analytically derive the exact expressions of the outage probability, the ergodic capacity and the finite-SNR diversity-multiplexing trade-off (DMT). Furthermore, the tight closed-form upper and lower bounds of the outage probability and the ergodic capacity are then developed. Moreover, the impact of the power splitting ratio is also evaluated and analyzed. Finally, we show that compared to the non-cooperative relaying scheme, the proposed protocol is a green solution to offer higher transmission rate and more reliable communication without consuming additional resource.