SYSTEM AND METHOD FOR FACILITATING AVOIDANCE OF WIRELESS CHARGING CROSS CONNECTION

• US 20140159653A1
• Filed: 09/17/2013
• Published: 06/12/2014
• Est. Priority Date: 12/12/2012
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Von Novak, William H., Kallal, Edward
• Granted Patent: US 9,660,478 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H04B 5/72 for local intradevice communication
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

A system and method for charging a chargeable device is provided. The system can include a wireless charger including a wireless power antenna and a wireless power transmitter coupled to the wireless power antenna and configured to generate a wireless charging field in at least one charging region. The wireless charging field includes a plurality of power signals. The wireless charger further includes a communication antenna and a transceiver coupled to the communication antenna and configured to communicate with the chargeable device via the communication antenna. The wireless charger further includes a controller configured to facilitate avoidance of cross connection of the chargeable device with the wireless charger and at least one other wireless charger in which the chargeable device receives power from the wireless power transmitter of the wireless charger while communicating with at least one other wireless charger. The system can include a chargeable device including a controller configured to generate a load pulse configured to be received by the wireless charger.

Claims

1. A wireless charger for charging a chargeable device, the wireless charger comprising:

a wireless power antenna;

a wireless power transmitter coupled to the wireless power antenna and configured to generate a wireless charging field in at least one charging region, the wireless charging field comprising a plurality of power signals;

a communication antenna;

a transceiver coupled to the communication antenna and configured to communicate with the chargeable device via the communication antenna; and

a controller configured to facilitate avoidance of cross connection of the chargeable device with the wireless charger and at least one other wireless charger in which the chargeable device receives power from one of the wireless charger or the at least one other wireless charger while communicating with the other of the wireless charger or the at least one other wireless charger.

2. The wireless charger of claim 1, wherein the controller is further configured to modulate the power signals by an amplitude that is sufficiently low so as to not affect power transmission but sufficiently high to be detected by the chargeable device.

3. The wireless charger of claim 2, wherein the controller is configured to modulate the power signals in a pattern that is unique to the wireless charger.

4. The wireless charger of claim 1, wherein the controller is further configured to detect an impedance change in the wireless charging field due to the chargeable device.

5. The wireless charger of claim 4, wherein the controller is configured to allow the wireless charger to accept out-of-band communication signals from the chargeable device during a predetermined period of time after the controller detects the impedance change in the wireless charging field being greater than a predetermined amount.

6. The wireless charger of claim 4, wherein the controller is configured to not allow the wireless charger to accept out-of-band communication signals for a period of time if the controller does not detect an impedance change in the wireless charging field being greater than a predetermined amount.

7. The wireless charger of claim 1, wherein the controller is further configured to detect whether a load pulse from the chargeable device and an advertisement from the chargeable device are concurrent with one another.

8. The wireless charger of claim 7, wherein the load pulse comprises an AC side impedance modulation.

9. The wireless charger of claim 7, wherein the load pulse comprises a DC side impedance modulation.

10. The wireless charger of claim 7, wherein, upon detecting a load pulse but not an advertisement from the chargeable device, the controller is further configured to extend a beacon mode time period.

11. The wireless charger of claim 7, wherein the load pulse comprises a single pulse of impedance modulation.

12. The wireless charger of claim 7, wherein the load pulse comprises a train of pulses or a tone burst of impedance modulation.

13. The wireless charger of claim 1, wherein the controller is further configured to communicate with the at least one other wireless charger to determine whether the wireless charger or the at least one other wireless charger is to be connected to the chargeable device.

14. The wireless charger of claim 13, wherein the wireless charger is connected to the chargeable device if the wireless charger has a larger received signal strength indication (RSSI) than does the at least one other wireless charger.

15. The wireless charger of claim 1, wherein the at least one charging region comprises a plurality of charging regions.

16. A chargeable device comprising:

a wireless power antenna configured to receive power from a wireless charger;

a wireless power receiver coupled to the wireless power antenna;

a communication antenna;

a transceiver coupled to the communication antenna and configured to communicate with the wireless charger via the communication antenna; and

a controller configured to generate a load pulse configured to be received by the wireless charger.

17. The chargeable device of claim 16, wherein the controller generates the load pulse prior to the chargeable device receiving power from the wireless charger.

18. A method of facilitating avoidance of cross connection of a chargeable device in communication with a wireless charger, the method comprising:

detecting an impedance change in a wireless charging field generated by the wireless charger, the impedance change caused by the chargeable device entering the wireless charging field;

evaluating the detected impedance change to determine whether the detected impedance change has a predetermined attribute; and

accepting out-of-band communication signals from chargeable devices during a first predetermined period of time after detecting an impedance change having the predetermined attribute.

19. The method of claim 18, wherein the predetermined attribute comprises an impedance change greater than a predetermined amount.

20. The method of claim 18, wherein the first predetermined period of time is in a range of one second to 10 seconds.

21. The method of claim 18, further comprising declining accepting out-of-band communication signals for a second period of time upon no impedance change being detected, and accepting out-of-band communication signals during a third predetermined period of time after detecting an impedance change not having the predetermined attribute.

22. A method of facilitating avoidance of cross connection of a chargeable device in communication with a wireless charger, the method comprising:

detecting a load pulse from a chargeable device;

detecting an out-of-band communication signal from a chargeable device;

evaluating a time period between detecting the load pulse and detecting the out-of-band communication signal; and

transmitting a response to the out-of-band communication signal if the time period is less than a predetermined time period.

23. The method of claim 22, wherein the predetermined time period is selected to be indicative of the load pulse and the out-of-band communication signal being sent by the same chargeable device.

24. The method of claim 22, further comprising, if the time period is less than the predetermined time period, placing the chargeable device on a list of accepted chargeable devices and beginning charging the chargeable device.

25. A method of facilitating avoidance of cross connection of a chargeable device in communication with a wireless charger, the method comprising:

detecting a communication signal from a chargeable device;

detecting an impedance change in a wireless charging field generated by the wireless charger within a first time period before or after receiving the communication signal, the impedance change caused by the chargeable device entering the wireless charging field; and

accepting additional communication signals from the chargeable device in response to determining a signal strength of the communication signal is above a signal strength threshold and that an amount of the impedance change is above an impedance change threshold.

26. The method of claim 25, wherein the communication signal is received via an out-of-band communication channel different than the wireless field, and wherein the communication signal is received during a beacon mode time period.