New Reconfigurable Nonlinear Energy Harvester: Boosting Rate-Energy Tradeoff

This paper proposes a new reconfigurable energy harvester for simultaneous wireless information and power transfer (SWIPT), where the energy harvester has multiple energy harvesting (EH) circuits in parallel and is adaptively reconfigured depending on the received power. Unlike the existing ideal linear EH model, where EH efficiency is a fixed constant regardless of the received power, we consider the practical nonlinear EH model. With the new reconfigurable energy harvester, we study adaptive mode switching between information decoding and EH over the fading channel. We optimize the problem of maximizing the average achievable rate under the energy causality condition, namely an average harvested energy constraint. Then we evaluate the rate-energy tradeoff for the proposed reconfigurable energy harvester. Numerical results demonstrate considerable performance gains through the proposed energy harvester. This implies that the SWIPT receiver can be self-powered effectively with the proposed one while meeting the energy causality safely.