A wireless power system includes a power source, power receiver, and components thereof. The system can also include a parasitic antenna that can improve the coupling to the power source in various modes. The antenna can have both a variable capacitor and a variable inductor, and both of those can be changed in order to change characteristics of the matching.

Packaging and details of a wireless power device

Exemplary embodiments are directed to wireless power transfer. A transmit antenna generates an electromagnetic field having a region for wirelessly transferring power from the transmit antenna to a plurality of receiver devices. A controller is operably coupled to the transmit antenna. The controller determines a power allocation for a particular one of the plurality of receiver devices disposed within the region, and adjusts the power allocation based at least in part on a power requirement received from the particular one of the plurality of receiver devices.

Adaptive power control for wireless charging of devices

Exemplary embodiments are directed to wireless power transfer. A transmitter (202) generates an electromagnetic field at a resonant frequency with a transmit antenna to create a coupling -mode region within a near field of the transmit antenna (204). The transmitter defines a beginning of a recurring period by on-off keying the electromagnetic field during a synchronization portion of the recurring period. During a power transmission portion of the recurring period, the transmitter couples portions of the electromagnetic field to different receive antennas of various receiver devices within the coupling -mode region. The transmitter also determines a power allocation within the recurring period for the various receiver devices disposed within the coupling -mode region and adjusts a power level of the near field radiation responsive to power requirements received from the receiver devices.

Adaptive power control for wireless charging

A dual-band antenna matching system and a method for dual-band impedance matching are provided. The method comprises: accepting a frequency-dependent impedance from an antenna; and, selectively supplying a conjugate impedance match for the antenna at either a first and a second communication band, or a third and a fourth communication band. More specifically, the method comprises: tuning a first tuning circuit to a first frequency; and, simultaneously tuning a second tuning circuit to a second frequency. In response, a conjugate match is supplied to the antenna in the first communication band in response to the first frequency. Simultaneously, the antenna is matched in the second communication band in response to the second frequency. When the first tuning circuit is tuned to a third frequency, and the second tuning circuit is tuned to a fourth frequency, then conjugate matches are supplied for the third and fourth communication bands, responsive to the third and fourth frequencies, respectively.

System and method for dual-band antenna matching

An impedance matching circuit includes a conductor line having an input port and an output port, a ground conductor, a tunable dielectric material positioned between a first section of the conductor line and the ground conductor, a non-tunable dielectric material positioned between a second section of the conductor line and the ground conductor, and means for applying a DC voltage between the conductor line and the ground conductor. The impedance matching circuit may alternatively include a first planar ground conductor, a second planar ground conductor, a strip conductor having an input port and an output port, and positioned between the first and second planar ground conductors to define first and second gaps, the first gap being positioned between the strip conductor and the first planar ground conductor and the second gap being positioned between the strip conductor and the second planar ground conductor. A non-tunable dielectric material supports the first and second planar ground conductors and the strip conductor in the same plane. A connection is provided for applying a DC voltage between the strip conductor and the first and second planar ground conductors. A plurality of tunable dielectric layer sections are positioned between the strip conductor and the first and second planar ground conductors so as to bridge the gaps between the said first and second planar ground conductors and the strip conductor at a plurality of locations, leaving non-bridged sections in between, defining a plurality of alternating bridged and non-bridged co-planar waveguide sections.

Tunable microwave devices with auto-adjusting matching circuit

An impedance matching arrangement is suitable for use with a frequency hopping radio communications system which is operable over a wide frequency band, so as to match the operating impedance of the antenna at each of the frequencies used. As the frequency of the radio system hops from one frequency to another, a note of any impedance mismatch is noted and data derived therefrom is stored for future use when that frequency is next selected so as to reduce any impedance mismatch.

Impedance matching arrangement

An impedance matching arrangement is suitable for use with a frequency hopping radio communications system which is operable over a wide frequency band, so as to match the operating impedance of the antenna 5 at each of the frequencies used. As the frequency of the radio system hops from one frequency to another, a note of any impedance mismatch is noted and data derived therefrom is stored at 7 for future use when that frequency is next selected so as to reduce any impedance mismatch. To preserve impedance matching values over long periods when the system is not used or when another antenna is used they are periodically entered into a memory 8 and can be down loaded back into memory 7 when required.

Deacon Malcolm John

Papers

Impedance matching arrangement

Impedance matching arrangement for an antenna