Information Processing and Wireless Energy Harvesting in Two-Way Amplify-and-Forward Relay Networks

Wireless energy harvesting is an efficient way to prolong the lifetime of energy constrained networks. In this paper, a two-way amplify-and-forward (AF) based relay network is considered, where two communicating nodes concurrently transmit there information signals to a relay node using time switching based relaying protocol (TSR). The relay node is energy constrained and therefore it first harvests the energy from the received radio frequency (RF) signals. After successful energy harvesting the relay utilizes the harvested energy to amplify and forward the received information signal to its destination. We derive the analytical expression for outage probability and achievable throughput at the receiving nodes. Our numerical results verify our analytical derivation and shows the effect of different system parameters on achievable throughput at receiving nodes.

I. Introduction

In recent years, energy harvesting through radio frequency (RF) signals has gain significant attention from the research society and industry. The idea is to prolong the wireless network lifetime through energy harvesting instead of recharging through conventional methods or replacing the batteries of low power nodes [1]. Other energy harvesting methods such as solar, wind, vibration, thermoelectric effects can also be used for recharging these nodes [2], [3]. However, these conventional techniques are unreliable and highly variable [4]. The main advantage of energy harvesting through RF signals over other conventional methods lies in the fact that RF signals can carry energy and information at the same time [5]. Therefore, these low power nodes will be able to procure energy and process the information simultaneously [6]–[10].