Multiband RF energy harvesting for zero-energy devices

Abstract

Radio frequency (RF) energy harvesting system scavenges energy from electromagnetic waves and supplies power wirelessly enabling the usage of zero-energy sensors or devices. Frequency band of the electromagnetic wave is an important parameter for energy harvesting systems. In this study, simultaneous multiband RF energy harvesting systems are analyzed both theoretically and experimentally for zero-energy devices. An advanced measurement system, which consists of an RF energy harvesting circuit, universal software radio peripherals (USRPs), and other equipment, is established to obtain received power and charging time samples for Industrial, scientific, and medical (ISM) and Global system for mobile communications (GSM) radio bands. The effects of each band and their different combinations on the charging time as well as the conversion parameter are thoroughly investigated for RF energy harvesting. According to a real-life communication scenario, the outage probabilities of wireless zero-energy sensors are presented. It is demonstrated in this study that the use of multiband frequencies in energy harvesting, in addition to the low-power requirement, increases the feasibility of zero-energy devices.