WIRELESS CHARGING OPTIMIZATION

• US 20150180266A1
• Filed: 12/23/2013
• Published: 06/25/2015
• Est. Priority Date: 12/23/2013
• Status: Abandoned Application

• Current Assignee: Qualcomm technologies international, ltd. (Qualcomm, Inc.)
• Original Assignee: Cambridge Silicon Radio Limited (Qualcomm, Inc.)
• Inventors: MCFARTHING, Anthony Lawrence
• Application Number:
  US14/138,393
• Publication Number:
  US 20150180266A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves
• 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: Y02B 40/00 Technologies aiming at improving the efficiency of home appliances, e.g. induction cooking or efficient technologies for refrigerators, freezers or dish washers

Abstract

Wireless charging methods and apparatus are disclosed, including a wireless charging method comprising transmitting a wireless charging signal using an antenna, determining an indication of power being transferred to at least one device being charged by the wireless charging signal, adjusting an impedance of the antenna to increase the power being transferred.

Claims

1. A wireless charging method comprising:

transmitting a wireless charging signal using an antenna;

determining an indication of power being transferred to at least one device being charged by the wireless charging signal; and

adjusting an impedance of the antenna to increase the power being transferred.

2. The method of claim 1, wherein determining the indication comprises determining characteristics of a signal supplied to the antenna.

3. The method of claim 1, wherein determining the indication comprises determining at least one of a current of a signal supplied to the antenna, the voltage of the signal, the relative phase of the current and the voltage, a power of the signal and the impedance of the antenna.

4. The method of claim 3, wherein determining the current comprises determining a voltage across a resistance that is in series with the antenna.

5. The method of claim 1, wherein adjusting the impedance of the antenna comprises adjusting at least one of a resistance and a reactance of the antenna.

6. The method of claim 1, wherein adjusting the impedance of the antenna comprises maximizing the power being transferred.

7. The method of claim 1, wherein adjusting the impedance of the antenna comprises reducing the reactance of the antenna.

8. The method of claim 1, wherein adjusting the impedance of the antenna comprises adjusting the impedance towards a target impedance or adjusting a load on a power amplifier connected to the antenna towards a target impedance.

9. The method of claim 1, wherein adjusting the impedance of the antenna comprises adjusting a variable capacitive divider coupled to the antenna.

10. A wireless charger comprising:

an antenna;

a transmitter coupled to the antenna for transmitting a wireless charging signal;

measurement apparatus for determining an indication of power being transferred to at least one device being charged by the wireless charging signal; and

a processor for adjusting an impedance of the antenna to increase the power being transferred.

11. The wireless charger of claim 10, wherein the measurement apparatus is arranged to determine the indication by determining characteristics of a signal supplied to the antenna.

12. The wireless charger of claim 10, wherein the measurement apparatus is arranged to determine the indication by determining at least one of a current of a signal supplied to the antenna, the voltage of the signal, the relative phase of the current and the voltage, a power of the signal and the impedance of the antenna.

13. The wireless charger of claim 12, further comprising a resistance in series with the antenna, and wherein the measurement apparatus is arranged to determine the indication by determining a voltage across the resistance.

14. The wireless charger of claim 10, wherein adjusting the impedance of the antenna comprises adjusting at least one of a resistance and a reactance of the antenna.

15. The wireless charger of claim 10, wherein the processor is arranged to adjust the impedance of the antenna to maximize the power being transferred.

16. The wireless charger of claim 10, wherein adjusting the impedance of the antenna comprises reducing the reactance of the antenna.

17. The wireless charger of claim 10, wherein adjusting the impedance of the antenna comprises adjusting the impedance towards a target impedance or adjusting a load on a power amplifier connected to the antenna towards a target impedance.

18. The wireless charger of claim 10, further comprising a variable capacitive divider coupled to the antenna, and wherein the processor is arranged to adjust the impedance of the antenna by adjusting the variable capacitive divider.