Choice of resonators for a WPT system in lossy materials

In order to cope with the necessity of transferring electric power through lossy dielectric materials such as house walls, human body or water, use of magnetically coupled resonator WPT system is recommended. A simple spiral resonator with series capacitance is the first candidate, followed by the second candidate, a little more sophisticated two layered spiral resonator with series capacitance. Since they confine electric energy in a narrow space effectively, the coupling becomes magnetic, which reduces dielectric loss appreciably.