Improving energy efficiency in dual-hop cooperative PLC relaying systems

Energy efficiency (EE) in multi-hop cooperative communication systems, both wireless and wired, is increasingly becoming more and more critical. This has recently been extended to include power line communications (PLC). In this respect, we propose in this paper to enhance the EE of a dual-hop amplify-and-forward (AF) cooperative relaying PLC system by considering energy-harvesting (EH) at the relay node. The energy harvester exploits the high noisy PLC channel feature as well as the transmitted signal power to forward the source information. In light of this, we derive an analytical expression for the EE and verify it with Monte Carlo simulations. The performance of the conventional relaying system, i.e. without any EH, is also considered to clearly quantify the achievable gains. The results show that the proposed system can considerably improve the EE of PLC systems and that increasing the channel variance will always make the proposed system more energy-efficient.