A Wideband, Quasi-Isotropic, Ambient RF Energy Harvester Combining UHF-TV and FM

Abstract

This letter demonstrates, through real-world field tests, an ambient radio frequency (RF) energy-harvesting system (fabricated on low-cost FR4) capable of harvesting from all surrounding ultrahigh-frequency (UHF) TV and FM towers in all UHF-TV and FM frequencies simultaneously to perpetually power a wireless sensor node. The system achieves -10 dB matching across the entire frequency bands. The UHF-TV portion harvested as much as 231 mu W(885 mu Wfor FM). The alignment-free, channel-agnostic nature demonstrates potential for ambient RF harvesting's adaption by users outside of the RF community who are not expected to be familiar with antenna alignment and frequency selection.