Adaptive matching and tuning of HF wireless power transmit antenna

• US 8,288,893 B2
• Filed: 07/17/2009
• Issued: 10/16/2012
• Est. Priority Date: 07/17/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Cook, Nigel P., Sieber, Lukas, Widmer, Hanspeter
• Primary Examiner(s): Deberadinis, Robert L.
• Application Number:
  US12/505,353
• Publication Number:
  US 20100117454A1
• Time in Patent Office: 1,187 Days
• Field of Search: 307/98
• US Class Current: 307/98
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06K 7/10178 including auxiliary means for focusing, repeating or boosting the electromagnetic interrogation field comparable booster antennas integrated on the record carrier itself G06K19/07794
• CPC Class Codes: G06K 7/10316 using at least one antenna particularly designed for interrogating the wireless record carriers antennas in general H01Q1/22
• CPC Class Codes: H01Q 21/30 Combinations of separate antenna units operating in different wavebands and connected to a common feeder system
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H01Q 7/005 with variable reactance for tuning the antenna

Abstract

Exemplary embodiments of the invention s are directed to a wireless power system with different coupling loops, such as two loops. The coupling loops are switched. One can be used for vicinity coupling, e.g., greater than a distance away, the other for proximity coupling, e.g., less than a distance away.

Claims

1. A transmitter system for wireless power, comprising:

an antenna resonant at a first frequency; and

a coupling loop assembly comprising;

a first coupling loop;

a first switch configured to activate said first coupling loop;

a second coupling loop; and

a second switch configured to activate said second coupling loop, the coupling loop assembly configured to couple with said antenna via magnetic induction.

2. A system as in claim 1, further comprising a controller configured to detect a coupling to the antenna, and to select either said first coupling loop or said second coupling loop based on said coupling.

3. A system as in claim 2, wherein said controller is configured to detect proximity coupling and to select said first coupling loop upon detecting proximity coupling.

4. A system as in claim 2, wherein said controller is configured to detect vicinity coupling and to select said second coupling loop upon detecting vicinity coupling.

5. A system as in claim 2, wherein said antenna includes multiple loops.

6. A system as in claim 5, further comprising a mechanism configured to adjust the position of said multiple loops relative to one another.

7. A system as in claim 2, wherein said coupling loop assembly is unconnected to said antenna.

8. A system as in claim 1, wherein said coupling loops are formed on a printed circuit board.

9. A system as in claim 1, wherein said antenna comprises multiple loops.

10. A system as in claim 9, further comprising a mechanism configured to adjust the position of said multiple loops relative to one another.

11. A transmitter system as in claim 1, further comprising a first circuit coupled to said antenna, and configured to cause production of a signal at the first frequency.

12. A system as in claim 1, further comprising a mechanism configured to adjust the position of said coupling loops relative to one another.

13. A receiver system for wireless power, comprising:

a circuit configured to receive a signal at a first frequency and to produce an electrical output based on said first frequency;

an antenna resonant at said first frequency; and

a coupling loop assembly comprising;

a first coupling loop;

a first switch configured to activate said first coupling loop;

a second coupling loop; and

a second switch configured to activate said second coupling loop.

14. A system as in claim 13, further comprising a controller configured to detect a coupling to the antenna, and to select either said first coupling loop or said second coupling loop based on said coupling.

15. A system as in claim 14, wherein said controller is configured to detect proximity coupling and to select said first coupling loop upon detecting proximity coupling.

16. A system as in claim 14, wherein said controller is configured to detect vicinity coupling and to select said second coupling loop upon detecting vicinity coupling.

17. A system as in claim 14, wherein said antenna includes multiple loops.

18. A system as in claim 17, further comprising a mechanism configured to adjust the position of said multiple loops relative to one another.

19. A system as in claim 14, wherein said coupling loop assembly is unconnected to said antenna and coupling between said coupling loop assembly and said antenna is performed via magnetic induction.

20. A system as in claim 13, wherein said coupling loops are formed on a printed circuit board.

21. A system as in claim 13, wherein said antenna includes multiple loops.

22. A system as in claim 21, further comprising a mechanism configured to adjust the position of said multiple loops relative to one another.

23. A system as in claim 13, further comprising a mechanism configured to adjust the position of said coupling loops relative to one another.

24. An antenna, comprising:

multiple loops forming an inductive part;

a capacitor, in series with said multiple loops; and

a mover, configured to move said multiple loops relative to one another, changing a resonance frequency of said antenna.

25. A system as in claim 24, wherein said mover comprises an electric motor.

26. A system as in claim 24, wherein said mover comprises a pneumatic motor.

27. A system as in claim 24, wherein said mover comprises a piezoelectric device.

28. A method of coupling electric power, comprising:

adjusting a coupling loop to transfer power via a first field upon detecting wireless power transfer via the first field between a pair of devices separated by less than a distance; and

adjusting the coupling loop to transfer power via a second field upon detecting wireless power transfer via the second field between the pair of devices separated by more than the distance.

29. A method as in claim 28, wherein said adjusting comprises switching to use a second coupling loop rather than the coupling loop.

30. A method as in claim 28, wherein adjusting comprises changing the size of the coupling loop.

31. A method as in claim 28, wherein adjusting comprises adjusting the position of the coupling loop relative to a second coupling loop.

32. The method as in claim 28, wherein the first field comprises a near-field.

33. The method as in claim 28, wherein the second field comprises a far-field.

34. A system comprising:

means, resonant at a first frequency, for transmitting or receiving wireless power; and

means for coupling wireless power to and from said means for transmitting or receiving, said coupling means including;

means for a first coupling of wireless power to said means for transmitting or receiving;

means for activating said first coupling means;

means for a second coupling of wireless power to said means for transmitting or receiving wireless power; and

means for activating said second coupling means.

35. A system as in claim 34, further comprising means for detecting a coupling to the means for transmitting or receiving wireless power, and selecting either said first coupling means or said second coupling means based on said detected coupling.

36. A system as in claim 35, wherein said means for detecting a coupling detects proximity coupling and selects said first coupling means upon detecting said proximity coupling.

37. A system as in claim 35, wherein said means for detecting a coupling detects vicinity coupling and selects said second coupling means upon detecting said vicinity coupling.

38. A system as in claim 34, wherein said first and second coupling means are formed on a printed circuit board.

39. A system as in claim 34, wherein said means for transmitting and receiving comprises multiple loops.

40. A system as in claim 39, further comprising means for adjusting the position of said multiple loops relative to one another.

41. A system as in claim 34, further comprising means for adjusting the position of said first and second coupling means relative to one another.

42. An antenna comprising:

means for producing inductive coupling;

means for adjusting a capacitance coupled in series with said means for producing inductive coupling; and

means for moving said means for inductive coupling, the means for moving configured to adjust a resonant frequency of the antenna based on a position of said means for producing inductive coupling.

43. A method of transmitting wireless power comprising:

detecting coupling to an antenna;

selecting a coupling loop based on said detected coupling; and

transferring wireless power from said coupling loop to said antenna via magnetic induction.

44. The method of claim 43, wherein detecting coupling comprises detecting proximity coupling.

45. The method of claim 43, wherein detecting coupling comprises detecting vicinity coupling.

46. The method of claim 43, wherein selecting a coupling loop comprises switching from another coupling loop to the selected coupling loop.

47. The method of claim 43, wherein selecting a coupling loop comprises adjusting a size of the selected coupling loop.

48. A method of receiving wireless power comprising:

detecting coupling to an antenna;

selecting a coupling loop based on the detected coupling;

receiving wireless power from the coupling loop at said antenna via magnetic induction; and

producing an electrical output based on said received wireless power.

49. The method of claim 48, wherein detecting coupling comprises detecting proximity coupling.

50. The method of claim 48, wherein detecting coupling comprises detecting vicinity coupling.

51. The method of claim 48, wherein selecting a coupling loop comprises switching from another coupling loop to the selected coupling loop.

52. The method of claim 48, wherein selecting a coupling loop comprises adjusting a size of the selected coupling loop.