Patent attributes
Embodiments of the invention are disclosed for generating a first alternating current in a resonant receiving coil at a resonant frequency in a self-resonant circuit tuned to resonate at substantially the same resonant frequency as a resonant transmitting coil in a self-resonant circuit of a wireless charger, the resonant receiving coil operating as a magnetically coupled resonator with the resonant transmitting coil. The separation distance between the two coils may be several times larger than geometric sizes of the coils. The embodiments convert the first alternating current in a power control circuit to a second alternating current at a different frequency than the resonant frequency. The embodiments drive a the power transmitting coil using the second alternating current to inductively couple with a proximately located power receiving coil in a user's device, to provide power to the power receiving coil in the user's device by contact-less electromagnetic induction.
