Enabling Far-Field Ambient Energy Harvesting Through Multi-Physical Sources
Résumé
Unlike near-field wireless power transfer based on the non-radiative inductive and magnetic resonant coupling which has already had a number of successful commercial applications, far-field radiofrequency (RF) ambient energy harvesting still trades its operation distance for a limited power density and low rectifying efficiency. Particularly, its low rectifying efficiency has been proved to be directly associated with rectifier's input power. Thus, by gathering more out of the available surrounding energy in the direct environment, the total dc output level can be efficiently enhanced. This paper reviews recent related works and provides a comprehensive picture of this idea through analytical modelling and experimental validation. It can be shown that a collaborative harvesting of multi-physical sources can be an effective solution to enable battery-free applications.