Abstract: A wearable sensor apparatus includes a band shaped and sized to be worn on a finger or limb of a user, a plurality of sensor coils configured to detect a magnetic field. A processor configured to calculate a position of the wearable sensor apparatus based upon signals from the plurality of sensor coils, and a communication module configured to transmit the position of the wearable sensor apparatus.

Abstract: A multi-mode wireless power transmitter includes a first drive circuit of a first type and a second drive circuit of a second type. The first drive circuit is configured to drive a first transmit coil at a first frequency. The second drive circuit is configured to drive a second transmit coil at a second frequency higher than the first frequency.

Abstract: Methods, apparatus and computer-readable storage media for performing foreign object detection (FOD) in a wireless power transfer system. A plurality of FOD measurements may be performed and processed to perform FOD.

Abstract: Apparatus and methods are described for performing wireless power transfer and foreign object detection with authentication at different power levels. The impact of time required for an authentication process to execute between transitions to different power levels is reduced.

Abstract: A wireless power transmitter and/or receiver and methods for operating the same are provided for maintaining an uninterrupted wireless power transfer. A wireless power transmitter and/or receiver adapt at least one wireless power transfer parameter according to at least one operating condition of the wireless power transmitter.

Abstract: Circuits for controlling magnetic-based tracking systems are described. These systems may be used in virtual reality applications, for example to track in real-time the location of one or more body parts. The systems use a beacon emitting mutually orthogonal magnetic fields. On the receiver side, one or more sensors disposed on different parts of a body receive the magnetic fields. The beacon includes switching amplifiers for driving the magnetic field emitters. Being binary, these amplifiers may be controlled by binary signals. The circuits may exhibit a resonant frequency response, and may be operated off-resonance, thus providing for a better control of the magnetic fields amplitude. As a result, however, fluctuations in the envelop of the magnetic fields due to the presence of a beating tone may arise. These fluctuations may be shortened by gradually activating the drivers for the magnetic field emitters.

Abstract: A sensor includes a ferromagnetic shield, at least one sensor coil disposed around an exterior of the ferromagnetic shield, and an electronics module within the ferromagnetic shield. The electronics module is configured to determine the position and/or orientation of the sensor based at least in part on a measurement of a signal induced in the at least one sensor coil.

Abstract: At least one component for a wireless power transmitter or a wireless power receiver. The at least one component includes a mechanical structure and/or circuitry configured to maintain and/or adjust a coupling coefficient K between the wireless power transmitter and the wireless power receiver, a loaded quality factor Q of the wireless power receiver, or both, such that K times Q is less than a constant.

Abstract: A wireless power transmitter can include a transmitting coil configured to wirelessly transmit power to a receiving coil. The wireless power transmitter can include a shield residing on a given side of a substrate spaced apart from the transmitting coil. The shield can be configured to filter an electric field induced by the transmitting coil.

Abstract: Methods, apparatus and computer-readable storage media for performing foreign object detection (FOD) in a wireless power transfer system. A plurality of FOD measurements may be performed and processed to perform FOD.

Abstract: Apparatus and methods are described for performing wireless power transfer and foreign object detection with authentication at different power levels. The impact of time required for an authentication process to execute between transitions to different power levels is reduced.

Abstract: An apparatus and method for performing foreign object detection for a wireless power transmitter. A matching network and transmit coil are energized, and a resonance is excited. The resonance is allowed to decay. A temporal characteristic of the decay is measured. The temporal characteristic is analyzed to determine whether a foreign object is coupled to an electromagnetic field generated by the transmit coil.

Abstract: A wireless power transmitter apparatus has a gap separating the first magnetic shield and the second magnetic shield, the gap having a magnetic permeability lower than that of the first magnetic shield and the second magnetic shield. A wireless power receiver apparatus has a conductive region within an area defined by a receive coil, the conductive region sized and positioned to inhibit operation of a wireless power transmitter not configured for wireless power transmission to the receive coil.

Abstract: A multi-mode wireless power transmitter includes a first drive circuit of a first type and a second drive circuit of a second type. The first drive circuit is configured to drive a first transmit coil at a first frequency. The second drive circuit is configured to drive a second transmit coil at a second frequency higher than the first frequency.

Abstract: Apparatus and methods for sensing current carried by one or more planar conductors is described. A plurality of sensing coils may be fabricated adjacent to one or more planar, current-carrying conductors. The sensing coils may detect a magnetic field generated by time-varying current flowing through the one or more planar conductors. The sensing coils may be arranged to cancel uniform and linear-gradient magnetic fields.

Abstract: Methods, apparatus and computer-readable storage media for performing foreign object detection (FOD) in a wireless power transfer system. A plurality of FOD measurements may be performed and processed to perform FOD.

Abstract: A multi-mode wireless power transmitter includes a first drive circuit of a first type and a second drive circuit of a second type. The first drive circuit is configured to drive a first transmit coil at a first frequency. The second drive circuit is configured to drive a second transmit coil at a second frequency higher than the first frequency.

Abstract: Apparatus and methods for sensing current carried by one or more planar conductors is described. A plurality of sensing coils may be fabricated adjacent to one or more planar, current-carrying conductors. The sensing coils may detect a magnetic field generated by time-varying current flowing through the one or more planar conductors. The sensing coils may be arranged to cancel uniform and linear-gradient magnetic fields.

Abstract: A FOD measurement may be performed to obtain a FOD measurement result. A confidence level as to whether a foreign object is present may be determined based on the FOD measurement result. One or more additional actions may be performed when the confidence level is within a predetermined range. The one or more additional actions may provide information to resolve whether a foreign object is present, to limit a level of power transfer, or both.

Abstract: Apparatus and methods for sensing current carried by one or more planar conductors is described. A plurality of sensing coils may be fabricated adjacent to one or more planar, current-carrying conductors. The sensing coils may detect a magnetic field generated by time-varying current flowing through the one or more planar conductors. The sensing coils may be arranged to cancel uniform and linear-gradient magnetic fields.