Wireless power transmission using small coupler for mobile devices

A small plane coupler integrating a receiving circuit is proposed and developed for wireless power transmission. A small and lightweight coupler has been required to enable a continuous wireless power in transmission systems for mobile devices. This coupler has two elements coupled with a two-dimensional waveguide sheet, and the coupling capacitances between the elements and the sheet reduce the coupler size by lowering their resonance frequencies. A propagation loss of -10.0 dB is obtained using the small 0.025-λ² coupler. Continuous operation of a mobile device was demonstrated by applying wireless power transmission to a two-dimensional waveguide sheet with the small plane coupler.