Ambient RF Energy Harvesting with Non-Linearities in Large-Scale Networks

Ambient radio-frequency (RF) energy harvesting is a potential solution for charging low-powered devices, as a result of its cost effectiveness and pervasiveness. In this paper, we deal with devices which are underlaid in a wireless communication network and harvest energy from the ambient RF transmitted signals. The devices are equipped with an array of multiple rectifying antennas, combined either at the RF or the DC domain, to increase the harvesting efficiency. A large-scale analysis is undertaken, with the use of stochastic geometry. We take into account the non-linearities of the RF energy harvesting process and derive closed-form analytical expressions for the average harvested energy for both array architectures. Our results show the importance of considering non-linearities, mainly in terms of the network's density and the size of the rectifying antenna array but also for other network parameters.