Abstract:
Systems, methods and apparatus are disclosed for a dual mode wireless power receiver. In accordance with on aspect, an apparatus for receiving wireless power is provided. The apparatus includes a first coil configured to wirelessly receive power from a first transmitter configured to generate a first alternating magnetic field having a first frequency. The apparatus further includes a second coil configured to wirelessly receive power from a second transmitter configured to generate a second alternating magnetic field having a second frequency higher than the first frequency. The second coil is positioned to enclose the first coil. A first coupling factor between the first coil and a coil of the first transmitter is higher than a second coupling factor between the second coil and a coil of the second transmitter when the first and second coils are positioned within respective charging regions of the first and second transmitters.
Abstract:
An aspect of this disclosure is an apparatus for receiving power wirelessly. The apparatus may be characterized by an impedance comprising a resistive component and a reactance component. The apparatus comprises an antenna circuit configured to receive power from a wireless charging field generated by a power transmitter, and to communicate with the power transmitter via a reflected signal, the reflected signal having a fundamental frequency. The apparatus may further comprise a control circuit coupled to the antenna circuit to generate the reflected signal. The reflected signal may be generated by performing at least one of: varying the resistive component of the impedance to generate a signal in the reflected signal having a frequency less than the fundamental frequency; and varying the reactance component of the impedance to change a phase of the reflected signal.
Abstract:
A uniform magnetic field may provide better performance in wireless power transmitters due to smaller impedance variations in an output of a power amplifier of a wireless power transmitter and also allow for wireless power transmitter pads to be thinner. One aspect of the disclosure provides a device for wireless power transfer. The device comprises a substantially planar transmit antenna that is configured to generate a magnetic field. The device also comprises a pad having a charging surface. At least a portion of the transmit antenna is disposed in the pad. The device also comprises a ferromagnetic material having a shape and a position relative to the transmit antenna. At least one of the shape or position of the ferromagnetic material, or a combination thereof, is selected to modify a distribution of the magnetic field at the charging surface.
Abstract:
This disclosure provides methods and apparatus for wirelessly transferring power. A first aspect of this disclosure is an apparatus for receiving power wirelessly. The apparatus comprises a receive circuit configured to receive wireless communication and charging power. The apparatus also comprises a metallic structure defining a gap extending from a first surface to a second surface, and through the metallic structure, the first surface opposite the second surface. The metallic structure is configured to receive the charging power from a wireless charging field oscillating at a first frequency. The metallic structure is further configured to convey the received power to the receive circuit via first and second connecting feeds. The metallic structure is also further configured to shield the receive circuit from interference at frequencies other than the first frequency.
Abstract:
A reconfigurable wireless power transmit antenna includes an antenna coil configured in a first configuration having a first number of turns configured to operate at a first frequency, the antenna coil configurable in a second configuration having a second number of turns configured to operate at a second frequency, and a switching mechanism configured to switch between the first configuration and the second configuration.
Abstract:
An electronic apparatus may include an electrically conductive body configured to magnetically couple to a first magnetic field. A first tuning element may be connected to the electrically conductive body. An electrically conductive coil may be wound about an opening defined by the electrically conductive body, and configured to magnetically couple to a second magnetic field.
Abstract:
Disclosed embodiments include magnetically coupling an externally generated magnetic field to a power receiving element arranged with a band that is configured to secure a wearable electronic device to a user. The power receiving element may extend a length of the band and traverse back and forth across a width of the band. Power induced in the power receiving element from the externally generated magnetic field may be generated to produce wirelessly received power for the wearable electronic device.
Abstract:
In one aspect, an apparatus for wirelessly coupling with other devices is provided. The apparatus includes a metallic cover having a removed portion. The apparatus comprises a first coil substantially wound around the removed portion of the metallic cover and configured to communicate with at least one other device via a communications protocol. The metallic cover comprises a second coil substantially wound around the removed portion of the metallic cover and configured to wirelessly and inductively receive charging power sufficient to charge or power the apparatus from at least one wireless charging power transmitter.