Systems and methods for forward link communication in wireless power systems

• US 9,166,439 B2
• Filed: 11/05/2012
• Issued: 10/20/2015
• Est. Priority Date: 11/05/2012
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Low, Zhen Ning, Jenwatanavet, Jatupum
• Primary Examiner(s): Dunn, Drew A
• Assistant Examiner(s): Robbins, Jerry D
• Application Number:
  US13/669,227
• Publication Number:
  US 20140125275A1
• Time in Patent Office: 1,079 Days
• Field of Search: 320/108
• US Class Current: 1/1
• CPC Class Codes: H02J 50/12 of the resonant type
• 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
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H04B 5/263 Multiple coils at either side
• CPC Class Codes: H04B 5/266 One coil at each side, e.g. with primary and secondary coils
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

This disclosure provides systems, methods and apparatus for forward link communication in wireless power systems. One aspect of the disclosure provides a wireless charging device for providing wireless power to a receiving device. The wireless charging device includes a primary transmit antenna configured to generate a wireless power field. The device further includes a parasitic antenna configured to selectively adjust a coupling between the primary transmit antenna and the receiving device. The device further includes a controller configured to control the selective adjustment of the parasitic antenna so as to communicate with the receiving device.

Claims

1. A wireless charging device for providing wireless power to a receiving device, the wireless charging device comprising:

a primary transmit antenna configured to generate a wireless power field;

a parasitic antenna configured to adjust a coupling between the primary transmit antenna and the receiving device;

a switching element electrically coupled to the parasitic antenna and configured to enable or disable the parasitic antenna; and

a controller configured to control the switching element electrically coupled to the parasitic antenna to adjust the coupling according to a pattern detectable by the receiving device, wherein the controller performs communication with the receiving device by the adjustment of the parasitic antenna.

2. The wireless charging device of claim 1, wherein said parasitic antenna is configured to adjust the coupling by varying a magnetic field strength of the wireless power field.

3. The wireless charging device of claim 1, wherein said parasitic antenna comprises a tuning capacitor and said switching element is electrically coupled in series with the tuning capacitor and the parasitic antenna.

4. The wireless charging device of claim 1, wherein said parasitic antenna comprises a variable resistor and/or a variable capacitor.

5. The wireless charging device of claim 1, wherein said parasitic antenna comprises a network of a plurality of reactive networks.

6. The wireless charging device of claim 1, wherein said parasitic antenna comprises a loop antenna.

7. The wireless charging device of claim 1, wherein said communication with the receiving device comprises transmitting data to the receiving device.

8. The wireless charging device of claim 7, wherein said communication with the receiving device comprises an in-band forward link.

9. The wireless charging device of claim 1, further comprising one or more additional parasitic antennas configured to independently adjust the coupling between the primary transmit antenna and one or more devices.

10. The wireless charging device of claim 9, wherein each parasitic antenna corresponds to a separate charging area of the wireless charging device.

11. A method of providing wireless power in a wireless charging device to a receiving device, comprising:

generating, at a primary transmit antenna, a wireless power field; and

controlling a switching element electrically coupled to a parasitic antenna to adjust a coupling between the primary transmit antenna and the receiving device, the coupling adjusted according to a pattern detectable by the receiving device wherein the wireless charging device performs communication with the receiving device by the adjustment of the parasitic antenna.

12. The method of claim 11, wherein said parasitic antenna is configured to adjust the coupling by varying a magnetic field strength of the wireless power field.

13. The method of claim 11, wherein said parasitic antenna comprises a tuning capacitor and said switching element is electrically coupled in series with the tuning capacitor and the parasitic antenna.

14. The method of claim 11, wherein said parasitic antenna comprises a variable resistor and/or a variable capacitor.

15. The method of claim 11, wherein said parasitic antenna comprises a network of a plurality of reactive networks.

16. The method of claim 11, wherein said parasitic antenna comprises a loop antenna.

17. The method of claim 11, further comprising transmitting data to the receiving device.

18. The method of claim 17, wherein said transmitting data to the receiving device comprises signaling the receiving device via an in-band forward link.

19. The method of claim 11, further comprising independently adjusting the coupling between the primary transmit antenna and one or more devices, via one or more additional parasitic antennas.

20. The method of claim 19, wherein each parasitic antenna corresponds to a separate charging area of the wireless charging device.

21. An apparatus for providing wireless power to a receiving device, comprising:

means for generating a wireless power field;

means for adjusting a coupling between the generating means and the receiving device, the adjusting means being parasitic to and galvanically isolated from the generating means;

means for switching electrically coupled to the adjusting means, the switching means configured to enable or disable the adjusting means; and

means for controlling the switching means electrically coupled to the adjusting means to adjust the coupling between the generating means and the receiving device, the coupling adjusted according to a pattern detectable by the receiving device, wherein the controlling means performs communication with the receiving device by the adjustment of the adjusting means.

22. The apparatus of claim 21, wherein said adjusting means comprises means for varying a magnetic field strength of the wireless power field.

23. The apparatus of claim 21, wherein said adjusting means comprises means for tuning and said switching means is electrically coupled in series with the tuning means and the adjusting means.

24. The apparatus of claim 21, wherein said adjusting means comprises means for varying resistance and/or means for varying capacitance.

25. The apparatus of claim 21, wherein said adjusting means comprises means for modifying reactance.

26. The apparatus of claim 21, wherein said adjusting means comprises a loop antenna.

27. The apparatus of claim 21, further comprising means for transmitting data to the receiving device.

28. The apparatus of claim 27, wherein said transmitting means comprises means for signaling the receiving device via an in-band forward link.

29. The apparatus of claim 21, further comprising means for independently adjusting the coupling between the generating means and one or more devices.

30. The apparatus of claim 29, wherein means for independently adjusting the coupling corresponds to one or more separate charging areas of the apparatus.

31. A non-transitory computer-readable medium comprising code that, when executed, causes an apparatus to:

generate, at a primary transmit antenna, a wireless power field;

control a switching element electrically coupled to a parasitic antenna to adjust a coupling between the primary transmit antenna and a receiving device,

the coupling adjusted according to a pattern detectable by the receiving device, wherein the apparatus performs communication with the receiving device by the adjustment of the parasitic antenna.

32. The medium of claim 31, wherein said parasitic antenna is configured to adjust the coupling by varying a magnetic field strength of the wireless power field.

33. The medium of claim 31, further comprising code that, when executed, causes the apparatus to transmit data to the receiving device.

34. The medium of claim 33, further comprising code that, when executed, causes the apparatus to signal the receiving device via an in-band forward link.