Wireless power beam device using microwave power transfer

The authors proposed a novel WPT system using ceramic dielectric resonators. Unloaded Q of ceramic resonator is several tens of thousands depending on the material. Thus, we can expect much longer transmission distance by using ceramic resonator. It was confirmed that the power transfer of this system was conducted by a combination both of coupling in non-radiated evanescent field and coupling through radiated wave. To utilize this eminent feature, horn antenna was installed at the aperture of the metal enclosure. The transmission distance became much longer owing to this structure. Some bulk of microwave energy, like an energy particle formed by the horn, was observed in the simulation. The possible application of this system is active tags without primary battery. The tags have secondary battery, which is charged when the beam from the transmitter is directed toward the tag.