NEAR FIELD TRANSMITTERS FOR WIRELESS POWER CHARGING

• US 20170187223A1
• Filed: 02/17/2016
• Published: 06/29/2017
• Est. Priority Date: 12/24/2015
• Status: Active Grant

• Current Assignee: Energous Corporation
• Original Assignee: Energous Corporation
• Inventors: HOSSEINI, Alister, LEABMAN, Michael A.
• Granted Patent: US 10,186,892 B2
• Time in Patent Office: Days
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves
• 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: H02J 7/0042 characterised by the mechanical construction
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals

Abstract

Disclosed is a system including RF circuitry configured to generate an RF signal; a plurality of unit cells configured to receive the RF signal and to cause an RF energy signal having a center frequency to be present within the unit cells; and receiver circuitry configured to charge an electronic device in response to an antenna of the electronic device receiving the RF energy signal when the antenna is tuned to the center frequency and positioned in a near-field distance from one or more of the unit cells.

Claims

1. A method for charging an electronic device, the method comprising:

leaking an RF energy signal from a charging surface in response to a metal structure being proximately positioned at a surface of the charging surface to cause the RF energy signal to enter a cavity formed between a structure of the charging surface and the metal structure so that an antenna of the electronic device can receive the leaked RF energy signal and route the received RF energy signal to a rectifier to convert the RF energy signal to charge a chargeable battery.

2. The method of claim 1, wherein the RF energy signal traverses in the cavity until the RF energy signal is received by the antenna of the electronic device.

3. The method of claim 1, wherein the metal structure, in being proximately positioned at the surface of the charging surface, is positioned within a near-field distance from the surface of the charging surface.

4. The method of claim 1, wherein the structure of the charging surface is a ground plane.

5. The method of claim 3, wherein the RF signal operates at a center frequency and the charging surface is configured to leak the RF signal when the antenna is tuned to the center frequency and positioned within the near-field distance from the surface of the charging surface.

6. The method of claim 1, wherein the metal structure and the surface of the charging surface are positioned substantially parallel with respect to each other.

7. The method of claim 1, wherein the antenna of the electronic device is positioned at a gap defined within the metal structure.

8. The method of claim 7, wherein the gap defined within the metal structure is positioned above at least a portion of the surface of the charging surface.

9. The method of claim 8, wherein the portion of the surface of the charging surface includes one or more unit cells.

10. A method for charging an electronic device, the method comprising:

applying an RF signal to a plurality of unit cells of a charging surface to cause an RF energy signal to be present within the unit cells of the charging surface; and

leaking the RF energy signal from one or more of the unit cells to a cavity formed between a structure of the charging surface and a metal portion of the electronic device positioned in a near-field distance from the one or more of the unit cells to cause an antenna of the electronic device to receive the RF energy signal for charging the electronic device.

11. The method of claim 10, wherein the RF energy signal is trapped between the structure of the charging surface and the metal portion of the electronic device until the RF energy signal is received by the antenna of the electronic device.

12. The method of claim 10, wherein the unit cells include a metamaterial.

13. The method of claim 10, wherein the RF energy signal operates at a center frequency and the unit cells are configured to leak the RF energy signal when the antenna is tuned to the center frequency and positioned within the near-field distance from the one or more of the unit cells.

14. The method of claim 10, wherein the structure of the charging surface is a ground plane.

15. A charging surface device comprising:

circuitry configured to generate an RF signal; and

a plurality of unit cells configured to receive the RF signal and to cause an RF energy signal to be present in the unit cells for charging an electronic device positioned in a near-field distance from one or more of the unit cells by leaking the RF energy signal from the one or more of the unit cells to a cavity formed between a structure of the charging surface and a metal portion of the electronic device to cause an antenna of the electronic device to receive the RF energy signal for charging the electronic device.

16. The device of claim 15, wherein the RF energy signal traverses between the surface of the charging surface and the metal portion of the electronic device until it is received by the antenna of the electronic device.

17. The device of claim 15, wherein the unit cells include a metamaterial.

18. The device of claim 15, wherein the RF energy signal operates at a center frequency and the one or more unit cells are configured to leak the RF energy signal when the antenna is tuned to the center frequency and positioned within the near-field distance from the one or more unit cells.

19. The device of claim 15, wherein the structure is a ground plane.