A relay apparatus in a wireless power transmission system includes a relay power reception antenna that receives power transmission alternating current power from a power transmission power transmission antenna, a relay rectifier that converts the power transmission alternating current power into relay direct current power, a relay inverter circuit that converts the relay direct current power into relay alternating current power, and a relay power transmission antenna that wirelessly transmits the relay alternating current power. When the relay apparatus has received binary relay received data, the relay apparatus reverses a sign of the binary relay received data and eliminates a difference between a first voltage of the relay direct current power and a second voltage of the relay direct current power on the basis of the reversed binary relay received data.

A device is described having one or more conductive loops to produce an electromagnetic field, such as for wireless power transfer to an electronic device. In some examples, an antenna is used with at least one resonating capacitor ring that is relatively co-planar with the antenna, and that is magnetically coupled to the antenna but is not electrically powered by an external source. In addition, a device is described having two or more thin-film coils, each coil comprising a pair of terminals and at least one loop defining a plane and an interior region. In some examples, the planes of the two or more coils are disposed substantially parallel to one another, the interior regions of the two or more coils at least partially overlap one another, and the pairs of terminals of the antennae are electrically connected in parallel.

A method and apparatus for inductively obtaining alternating current from a first variable magnetic field with an input coil; forming with an output coil a second variable magnetic field using the alternating current; and conducting the alternating current from the input coil to the output coil.

A method and apparatus for inductively obtaining alternating current from a first variable magnetic field with an input coil; forming with an output coil a second variable magnetic field using the alternating current; and conducting the alternating current from the input coil to the output coil.

A contactless power transfer system is provided. The contactless power transfer system includes a first power exchanging coil configured to exchange power, a power mating coil operatively coupled to a switching unit, and a controller operatively coupled to the switching unit. The controller is configured to control switching operations of the switching unit to actively control a current in the power mating coil to match an impedance of the first power exchanging coil and enable the exchange of power.

A relay apparatus in a wireless power transmission system includes a relay power reception antenna that receives power transmission alternating current power from a power transmission power transmission antenna, a relay rectifier that converts the power transmission alternating current power into relay direct current power, a relay inverter circuit that converts the relay direct current power into relay alternating current power, and a relay power transmission antenna that wirelessly transmits the relay alternating current power. When transmitting data to the power transmission apparatus through amplitude modulation, the relay apparatus varies amplitude of voltage of the power transmission alternating current power received by the relay power reception antenna between a first amplitude and a second amplitude and performs control for eliminating a difference between a third amplitude of the relay alternating current power and a fourth amplitude of the relay alternating current power.

A wireless power transmitter includes a converter configured to output an alternating current (AC) voltage in response to a transmission control signal; a power transmitter including a power transmitting coil and configured to vary an impedance in response to a resonance control signal, and to receive the AC voltage to wirelessly transmit power; and a controller configured to determine whether a wireless power receiver is present while varying the transmission control signal and the resonance control signal.

A resonator structure for wireless power transfer includes a first piece and a second piece of magnetic material disposed adjacent to one another, a spacer disposed between the first and second pieces of magnetic material forming a gap of 1 mm or less between the first and second pieces of magnetic material, and an electrical conductor wound to form a plurality of loops. The electrical conductor is disposed on the first and second pieces of magnetic material. The resonator structure includes a thermal conductor positioned in contact with the electrical conductor and at least one of the first and second pieces of magnetic material.

A system and method for scaling distributed device arrays, which include displays and sensor arrays improving the performance of arrays of virtually all sizes by combining wireless addressing and powering of functional devices including individual array elements or sub-sectors, groups, or collections of array elements using tap couplers distributed in a wireless relay system.

Described herein are improved configurations for a wireless power transfer for electronic devices that include at least one source magnetic resonator including a capacitively-loaded conducting loop coupled to a power source and configured to generate an oscillating magnetic field and at least one device magnetic resonator, distal from said source resonators, comprising a capacitively-loaded conducting loop configured to convert said oscillating magnetic fields into electrical energy, wherein at least one said resonator has a keep-out zone around the resonator that surrounds the resonator with a layer of non-lossy material.