Generator unit for wireless power transfer

• US 10,320,242 B2
• Filed: 11/24/2014
• Issued: 06/11/2019
• Est. Priority Date: 11/09/2012
• Status: Active Grant

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Hajimiri, Seyed Ali, Bohn, Florian, Abiri, Behrooz
• Primary Examiner(s): Fureman, Jared
• Assistant Examiner(s): Evans, James
• Application Number:
  US14/552,414
• Publication Number:
  US 20150130293A1
• Time in Patent Office: 1,660 Days
• CPC Class Codes: H01Q 21/225 Finite focus antenna arrays
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves
• CPC Class Codes: H02J 50/23 characterised by the type of transmitting antennas, e.g. directional array antennas or Yagi antennas
• CPC Class Codes: H02J 50/40 using two or more transmitting or receiving devices H02J50/50 takes precedence
• CPC Class Codes: H02J 50/402 the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment

Abstract

An RF signal generator wirelessly transferring power to a wireless device includes, in part, a multitude of generating elements generating a multitude of RF signals transmitted by a multitude of antennas, a wireless signal receiver, and a control unit controlling the phases and/or amplitudes of the RF signals in accordance with a signal received by the receiver. The signal received by the receiver includes, in part, information representative of the amount of RF power the first wireless device receives. The RF signal generator further includes, in part, a detector detecting an RF signal caused by scattering or reflection of the RF signal transmitted by the antennas. The control unit further controls the phase and/or amplitude of the RF signals in accordance with the signal detected by the detector.

Claims

1. An RF signal generator adapted to wirelessly transfer power to a first wireless device, said RF signal generator comprising:

a first plurality of generating elements each adapted to generate an RF signal, the plurality of the RF signals being transmitted by a first plurality of antennas;

a wireless signal receiver;

a control unit adapted to control a phase of the RF signal generated by each of the first plurality of RF signal generating elements in accordance with a first signal the receiver receives from the first wireless device, said first signal comprising information representative of an amount of RF power the first wireless device receives, and

a detector adapted to detect an RF signal caused by scattering or reflection of the RF signal transmitted by the first plurality of antennas, wherein said control unit is further adapted to control a phase of the RF signal generated by each of the first plurality of RF signal generating elements in accordance with the signal detected by the detector.

2. The RF signal generator of claim 1 wherein said control unit is further adapted to control an amplitude of the RF signal generated by each of the plurality of RF signal generating elements.

3. The RF signal generator of claim 1 wherein said RF signal generator is adapted to wirelessly transfer power to the first wireless device using time-domain multiplexing.

4. The RF signal generator of claim 1 wherein said RF generator is further adapted to power a second wireless device, said RF signal generator transferring power to the first and second wireless devices using time-domain multiplexing.

5. The RF signal generator of claim 1, wherein said RF signal generator further comprises a second plurality of generating elements each adapted to generate an RF signal, said control unit being further adapted to cause one of the first plurality of generating elements or the second plurality of generating elements to generate RF signals during a first time period.

6. The RF signal generator of claim 1 wherein said RF signal generator further comprises a second plurality of generating elements each adapted to generate an RF signal, said first and second plurality of generating elements each adapted to generate an RF signal in accordance with a reference timing signal supplied by the control unit during a first time period.

7. The RF signal generator of claim 1 wherein said RF signal generator is integrated on a semiconductor die.

8. The RF signal generator of claim 1 wherein said RF signal generator is adapted to receive a second plurality of generating elements in a modular fashion thereby enabling the control unit to control a phase and amplitude of the RF signal generated by each of the second plurality of RF signal generating elements in accordance with the first signal the receiver receives from the first wireless device.

9. The RF signal generator of claim 1 further comprising a plurality of control locked loops adapted to provide timing signals used in varying the phases of the RF signals generated by the RF signal generating elements.

10. The RF signal generator of claim 1 further comprising a plurality of phase rotators adapted to vary the phases of the RF signals generated by the RF signal generating elements.

11. The RF signal generator of claim 1 wherein said control unit is further adapted to control the amplitude of the RF signal generated by each of the first plurality of RF signal generating elements in accordance with the signal detected by the detector.

12. A method of powering a first wireless device using radio frequency (RF) signals, the method comprising:

transmitting a first plurality of RF signals via a first plurality of antennas;

receiving a first signal from the first wireless device;

controlling phases of the first plurality of RF signals in accordance with the first signal, said first signal comprising information representative of an amount of RF power the first wireless device receives,

detecting a scattered RF signal caused by scattering or reflection of the RF signal transmitted by the first plurality of antennas, and

controlling a phase of the each of the first plurality of RF signals in accordance with the detected RF signal.

13. The method of claim 12 further comprising:

controlling amplitudes of the RF signals in accordance with the first signal.

14. The method of claim 12 further comprising:

transmitting the first plurality of RF signals using time-domain multiplexing.

15. The method of claim 12 further comprising

transmitting a second plurality of RF signals, wherein each of said first and second plurality of RF signals is generated in accordance with a reference timing signal supplied by a control unit during a first time period.

16. The method of claim 12 further comprising:

generating the first plurality of RF signals via a first plurality of generating elements formed on a semiconductor substrate, said semiconductor substrate further comprising a receiving unit receiving the first signal from the first wireless device, said semiconductor substrate further comprising a controller controlling the phases of the first plurality of RF signals.

17. The method of claim 12 further comprising:

generating the first plurality of RF signals via a first plurality of generating elements disposed in a generating unit, said generating unit being adapted to receive a second plurality of generating elements in a modular fashion.

18. The method of claim 12 further comprising:

controlling the phases of the first plurality of RF signals in accordance with a timing signal generated by at least one control locked loop.

19. The method of claim 12 further comprising:

controlling the phases of the first plurality of RF signals using a plurality of phase rotators.

20. The method of claim 12 further comprising:

controlling the phases of the first plurality of RF signals using timing signals delivered via a tree-like distribution network.

21. The method of claim 12 further comprising:

controlling amplitudes of the RF signals in accordance with the first signal.

22. The method of claim 12 further comprising:

transmitting the first plurality of RF signals using time-division multiplexing.

23. The method of claim 12 further comprising:

transmitting a second plurality of RF signals, wherein each of said first and second plurality of RF signals is generated in accordance with a reference timing signal supplied by a control unit during a first time period.