Abstract:
Energy efficiency in multihop cooperative power-line
communication (PLC) systems has recently received considerable
attention in the literature. In order to make such systems more energy efficient, this paper proposes a relaying technique equipped
with energy-harvesting capabilities. More specifically, we consider
a dual-hop decode-and-forward (DF) broadband PLC relaying system in which the relay exploits the high noise inherent in PLC
channels to further enhance energy efficiency; this system will be
referred to as DF with energy harvesting (DF-EH). This study deploys, particularly, the time-switching relaying protocol for energy
harvesting. An accurate analytical expression for the energy efficiency and a closed-form expression for the average outage probability of the proposed system are derived and then verified with
Monte Carlo simulations. For the sake of comparison and to highlight the achievable gains, we also analyze the energy-efficiency performances and the average outage probabilities of the conventional
DF relaying system, i.e., without energy harvesting, as well as that
of the direct-link approach. Furthermore, various frequency selection and power allocation strategies, namely, optimal frequency
selection, random frequency selection, and equal power allocation,
exploiting the multiple power cables, are studied. Then, the impact of several system parameters such as the energy-harvesting
time factor, various idle power consumption profiles, relay location,
power allocation as well as different noise scenarios are examined.
The results reveal that the proposed DF-EH system is able to provide energy efficiency improvements of more than 30% compared
to the conventional DF relaying scheme. It is also shown that the
proposed system with optimal frequency selection performs better
at low SNR, whereas at high SNR the equal power allocation based
system will have the best performance.
