Headset Charge via Short-Range RF Communication

• US 20100203831A1
• Filed: 02/06/2009
• Published: 08/12/2010
• Est. Priority Date: 02/06/2009
• Status: Active Grant

• Current Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: MUTH, James Michael
• Granted Patent: US 8,213,862 B2
• Time in Patent Office: Days
• US Class Current: 455/41.200
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves
• 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: H04M 1/6066 including a wireless connection

Abstract

Embodiments of the present invention enable energy transfer via short-range RF communication between a main device and an associated device, thereby allowing the main device to energy charge the associated device. Accordingly, the need for a separate charger for the associated device can be eliminated. Embodiments of the present invention are suitable for applications in which the main device and the associated device operate in close proximity to each other. Further, embodiments of the present invention are suitable for applications in which the associated device is more energy-constrained than the main device. According to embodiments, energy transfer applications can be supported using near field communication (NFC). In an embodiment, energy transfer via NFC is enabled between a Bluetooth enabled cellular phone and a Bluetooth headset. In another embodiment, energy transfer via NFC is enabled between a Bluetooth enabled digital camera and a Bluetooth enabled digital frame.

Claims

1. A method of energy charging a Bluetooth headset via a short-range RF communication technology, comprising:

receiving radio frequency (RF) energy at a RF tag of the Bluetooth headset from a RF tag reader of a cellular phone;

converting the received RF energy to a DC signal; and

providing the DC signal to a storage battery of the Bluetooth headset.

2. The method of claim 1, further comprising:

receiving an activation signal at the RF tag of the Bluetooth headset from the RF tag reader of the cellular phone.

3. The method of claim 1, further comprising:

establishing Bluetooth pairing with the cellular phone via the short-range communication technology with the RF tag reader of the cellular phone.

4. The method of claim 1, further comprising:

receiving an energy charging start signal at the RF tag of the Bluetooth headset from the RF tag reader of the cellular phone; and

transmitting an acknowledgment signal in response to the energy charging start signal from the RF tag of the Bluetooth headset to the RF tag reader of the cellular phone.

5. The method of claim 1, further comprising:

transmitting an energy charging termination signal from the RF tag of the Bluetooth headset to the RF tag reader of the cellular phone when the storage battery is fully charged.

24. The method of claim 1, wherein the short-range RF communication technology is near field communication (NFC), and wherein the RF tag includes a NFC tag and the RF tag reader includes a NFC reader.

6. A method of energy charging a Bluetooth headset via a short-range communication technology, comprising:

transmitting an energy charging start signal from a RF tag reader of a cellular phone to a RF tag of the Bluetooth headset;

determining a radio frequency (RF) transmit power level of the RF tag reader of the cellular phone; and

transmitting RF energy at the determined RF transmit power level from the RF tag reader of the cellular phone to the RF tag of the Bluetooth headset.

7. The method of claim 6, further comprising:

transmitting an activation signal from the RF tag reader of the cellular phone to the RF tag of the Bluetooth headset.

8. The method of claim 6, further comprising:

receiving an acknowledgment signal in response to the energy charging start signal at the RF tag reader of the cellular phone from the RF tag of the Bluetooth headset.

9. The method of claim 6, further comprising:

establishing pairing with the Bluetooth headset via the short-range communication technology with the RF tag of the Bluetooth headset.

10. The method of claim 6, further comprising:

receiving a control signal; and

terminating RF energy transmission from the RF tag reader of the cellular phone to the RF tag of the Bluetooth headset in response to the received control signal.

11. The method of claim 10, wherein the control signal is due to an energy charging termination signal received by the RF tag reader of the cellular phone from the RF tag of the Bluetooth headset.

12. The method of claim 10, wherein the control signal is due to a user command by a user of the cellular phone.

13. The method of claim 10, wherein the control signal is due to a loss of short-range communication with the RF tag of the Bluetooth headset.

14. The method of claim 10, wherein the control signal is due to a battery level of the cellular phone dropping below a determined threshold.

15. The method of claim 10, wherein the control signal is due to disconnecting the cellular phone from an AC power source.

16. The method of claim 6, wherein the RF transmit power level of the RF tag reader is determined based on one more of (a) an energy level of a battery of the cellular phone;

and (b) whether or not the cellular phone is connected to an AC power source.

17. The method of claim 6, further comprising:

increasing the determined RF transmit power level when the cellular phone becomes connected to an AC power source.

25. The method of claim 6, wherein the short-range RF communication technology is near field communication (NFC), and wherein the RF tag includes a NFC tag and the RF tag reader includes a NFC reader.

18. A Bluetooth headset, comprising:

a Bluetooth transceiver configured to communicate via Bluetooth with a respective Bluetooth transceiver of a cellular phone;

a RF tag configured to receive radio frequency (RF) energy from a RF tag reader; and

a RF to DC converter configured to convert the received RF energy into a DC signal and to provide the DC signal to a storage battery of the Bluetooth headset, thereby energy charging the storage battery.

19. The Bluetooth headset of claim 18, wherein the RF tag is further configured to identify the Bluetooth headset to the RF tag reader.

20. The Bluetooth headset of claim 18, wherein the RF tag is further configured to Bluetooth pair the Bluetooth headset with the cellular phone.

21. The Bluetooth headset of claim 18, wherein the RF tag is further configured to receive an energy charging start signal from the RF tag reader and to transmit an acknowledgment signal in response to the energy charging signal to the RF tag reader.

22. The Bluetooth headset of claim 18, wherein the RF tag is further configured to transmit an energy charging termination signal to the RF tag reader when the storage battery of the Bluetooth headset is fully charged.

23. The Bluetooth headset of claim 18, wherein the RF to DC converter is integrated within the RF tag.

26. The Bluetooth headset of claim 18, wherein the RF tag includes a near field communication (NFC) tag, and wherein the RF tag reader includes a NFC reader.