Joint Design of Relay-User Selection in Direct-link Energy Harvesting Relay Networks

In this paper, we investigate the outage performance of the proposed relay-user selection (RUS) scheme for amplify-and-forward full-duplex multi-relay multi-user network, where the direct link between the source node and the user node is used to convey information. Meanwhile, each relay node is energy-constrained and the simultaneous wireless information and power transfer technology is employed to harvest energy. A power splitter is equipped in each relay node to split the received signal into energy harvesting part and signal processing part. The closed-form and a simple asymptotic expression for outage probability is provided. Moreover, the optimal power splitting factor of each relay node is calculated to minimize the outage probability of the system. Finally, the numerical simulations are provided to validate the analysis.