Wireless Power Transfer: Survey and Roadmap
Xiaolin Mou, Student Member, IEEE and Hongjian Sun, Member, IEEE
"There are three categories of Wireless Power Transfer (WPT) technologies: inductive coupling, magnetic resonant coupling, and electromagnetic
Chargine a phone
Wireless power transmission safely charges devices anywhere within a room
February 16, 2017
Wireless Power Transfer (WPT)
"There are three categories of Wireless Power Transfer (WPT) technologies: inductive coupling, magnetic resonant coupling, and electromagnetic radiation."
Here is an example of magnetic resonance coupling using "Quasistatic cavity resonance (QSCR)".
https://phys.org/news/2017-02-wireless-power-transmission-safely-devices.html (Link by Suja Vijayan)
1. Induction of electrical currents in metalized walls generates uniform magnetic fields in a room.
2. Receiving coils that operate in the same resonant frequency as the magnetic fields pick up the magnetic field and the energy it contains.
3. If the coil is part of a cell phone charger, the transferred energy will be transformed to electric energy that charges the phone.
Matthew J. Chabalko et al, Quasistatic Cavity Resonance for Ubiquitous Wireless Power Transfer, PLOS ONE (2017). DOI: 10.1371/journal.pone.0169045
Note Figure 5 demonstrating "Specific absorption rate" (SAR) analysis (rate at which energy is absorbed by a person)