ANTENNA FOR AN ELECTRONIC DEVICE

• US 20160181696A1
• Filed: 08/25/2015
• Published: 06/23/2016
• Est. Priority Date: 12/18/2014
• Status: Active Grant

• Current Assignee: STMicroelectronics SAS (STMicroelectronics NV)
• Original Assignee: STMicroelectronics SAS (STMicroelectronics NV)
• Inventors: Rizzo, Pierre
• Granted Patent: US 10,020,580 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 1/48 Earthing means; Earth screens; Counterpoises
• CPC Class Codes: H01Q 1/50 Structural association of antennas with earthing switches, lead-in devices or lightning protectors
• CPC Class Codes: H01Q 1/528 reducing the re-radiation of a support structure in a parabolic reflector antenna H01Q19/023
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop

Abstract

A radio or power transfer antenna, in the form of a planar conductive winding, with one of two ends of the planar conductive winding directly connected to a metal section or plane which continuously surrounds the planar conductive winding.

Claims

1. A radio or power transfer antenna, in the form of a planar conductive winding, wherein one of the two ends of the planar winding is directly connected to a metal section or plane which continuously surrounds the planar conductive winding.

2. The antenna of claim 1, wherein the metal section or plane is intended to be grounded.

3. The antenna of claim 1, wherein the end connected to the section or plane is the external end of the winding.

4. The antenna of claim 1, wherein the plane comprises an opening having the planar winding placed therein.

5. The antenna of claim 1, wherein the winding is inscribed within an external diameter in the range from approximately 5 to approximately 20 mm.

6. The antenna of claim 1, wherein the center of the winding is inscribed within a diameter in the range from 2 to 5 mm.

7. A radio frequency circuit, comprising:

an antenna including a planar conductive winding having two ends and where one of the two ends is directly connected to a metal section which continuously surrounds the planar conductive winding;

a contactless front end circuit; and

a matching network coupled between the contactless front end circuit and the antenna, wherein the matching network includes a first capacitive element provided between each end of the planar conductive winding and a corresponding terminal of the contactless front end circuit.

8. The circuit of claim 7, wherein the matching network further comprises a second capacitive element connecting the two ends of the planar conductive winding.

9. An electronic device, comprising:

electronic circuitry; and

a radio frequency circuit coupled to the electronic circuitry, the radio frequency circuit including,

an antenna having a planar conductive winding with two ends, one of the ends being directly connected to a metal plane that continuously surrounds the planar conductive winding;

a contactless front end circuit including a plurality of terminals; and

a matching network coupled between the contactless front end circuit and the antenna, wherein the matching network includes a first capacitive element connected between each end of the planar conductive winding and a corresponding one of the terminals of the contactless front end circuit.

10. The electronic device of claim 9, wherein an opening of the metal plane in which the antenna is located is also configured to receive a camera, a microphone, or a light sensor.

11. The electronic device of claim 10, wherein the electronic circuitry comprises cell phone circuitry.

12. The electronic device of claim 11, wherein the metal plane comprises a cell phone shell.

13. A method, comprising:

forming a planar antenna within an opening of a metal plane, the metal plane completely surrounding the planar antenna and the planar antenna including first and second ends;

connecting the first end of the planar antenna directly to the metal plane; and

isolating a common mode signal on the first and second ends of the planar antenna from a communications circuit configured to be coupled to the first and second ends of the planar antenna.

14. The method of claim 13, wherein forming the planar antenna within the opening of the metal plane comprises forming a planar conductive winding within the opening of the metal plane.

15. The method of claim 14, wherein forming the planar conductive winding within the opening of the metal plane comprises forming one of a circular planar conductive winding and a square-shaped planar conductive winding within the opening of the metal plane.

16. The method of claim 13, wherein isolating a common mode signal on the first and second ends of the planar antenna from the communications circuit comprises capacitively coupling the first and second ends of the planar antenna to the communications circuit.

17. The method of claim 13 further comprising capacitively coupling the first and second ends of the planar antenna.

18. The method of claim 13 further comprising forming the opening in the metal plane, the opening having a shape that is either a circular shape or a square shape.

19. The method of claim 13 further comprising performing active retromodulation of signal being communicated by the planar antenna.

20. The method of claim 13 wherein isolating the common mode signal on the first and second ends of the planar antenna from the communications circuit includes matching the planar antenna and the communications circuit.