TRANSMITTING MAGNETIC FIELD THROUGH METAL CHASSIS USING FRACTAL SURFACES

• US 20140011447A1
• Filed: 11/16/2012
• Published: 01/09/2014
• Est. Priority Date: 07/03/2012
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Konanur, Anand S, Karacaoglu, Ulun, Yang, Songnan
• Granted Patent: US 9,225,388 B2
• Time in Patent Office: Days
• US Class Current: 455/41.1
• CPC Class Codes: H01Q 1/2266 disposed inside the computer
• CPC Class Codes: H01Q 1/36 Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewithH01Q1/08, H01Q1/14 take precedence
• CPC Class Codes: H01Q 1/50 Structural association of antennas with earthing switches, lead-in devices or lightning protectors
• CPC Class Codes: H01Q 1/52 Means for reducing coupling between antennas; Means for reducing coupling between an antenna and another structure absorbing means H01Q17/00
• 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
• CPC Class Codes: H04B 5/00 Near-field transmission systems, e.g. inductive or capacitive transmission systems
• CPC Class Codes: H04B 5/26 using coils

Abstract

Described herein are techniques related one or more systems, apparatuses, methods, etc. for reducing induced currents in a apparatus chassis. For example, a fractal slot is constructed in the apparatus chassis to reduce the induced currents, and enhance passage of magnetic fields through the apparatus chassis. In this example, the fractal slot may include a no-self loop fractal space filling curve shape to provide high impedance to the induced currents.

Claims

1. An apparatus comprising:

one or more processors;

a memory coupled to the one or more processors;

a near field communications (NFC) antenna coupled to the one or more processors wherein the NFC antenna is integrated underneath a metal chassis of the apparatus; and

at least one fractal slot constructed on the metal chassis, the at least one fractal slot has no-self loop fractal space filling curve template and is tiled with another fractal slot to cover an area defined at least by outside parameter of the NFC antenna.

2. The apparatus as recited in claim 1, wherein the metal chassis includes an embedded or attached conductive coating, the conductive coating is located between the metal chassis and the NFC antenna.

3. The apparatus as recited in claim 1, wherein the at least one fractal slot is constructed to include slices that extend from a conductive coating and penetrate the metal chassis.

4. The apparatus as recited in claim 1, wherein the at least one fractal slot defines an area in a conductive coating, the area includes grounding points at both ends of the at least one fractal slot to provide electrostatic discharge (ESD) protection.

5. The apparatus as recited in claim 1, wherein the no-self loop fractal space filling curve template includes a Hilbert Curve, a Peano Curve, a Lebesque Curve, or an H-tree curve.

6. The apparatus as recited in claim 1, wherein the no-self loop fractal space filling curve template includes a continuous slot line to define the at least one fractal slot.

7. The apparatus as recited in claim 1, wherein the fractal slots are tiled to define an area in a conductive coating, the area covers an approximate extent of electromagnetic fields that induce Eddy current to the conductive coating.

8. The apparatus as recited in claim 1, wherein the no-self loop fractal space filling curve template includes a geometric pattern configured to cut continuity of a smaller scale Eddy current, the geometric pattern is defined by a transformation function that is re-generated to model an area defined by approximate extent of electromagnetic fields that induce larger scale Eddy current.

9. The apparatus as recited in claim 1, wherein the fractal slot is tiled into different quadrants of an area covering an approximate extent of electromagnetic fields that induce Eddy current to a conductive coating.

10. The apparatus as recited in claim 1, wherein the at least one fractal slot includes an adjustable width to provide high impedance to Eddy current and frequency selectivity when the NFC antenna is operating in wireless fidelity (WiFi) signal frequency.

11. A apparatus chassis comprising:

a fractal slot to include a no-self loop fractal space filling curve shape, wherein the fractal slot is tiled with another fractal slot to cover an area defined at least by an outside loop of a near field communications (NFC) antenna that is integrated underneath the fractal slots; and

a conductive coating that is integrated between the NFC antenna and the tiled fractal slots.

12. The apparatus in claim 11, wherein the fractal slot is constructed on a metallic chassis or carbon-fiber chassis.

13. The apparatus in claim 11, wherein the fractal slot is constructed to include segments that extend from the conductive coating to the metal chassis.

14. The apparatus in claim 11, wherein the fractal slot defines an area in the conductive coating, the area includes grounding points at both ends of the fractal slot to provide electrostatic discharge (ESD) protection.

15. The apparatus in claim 11, wherein the fractal slot includes an adjustable width to provide high impedance to induced currents and frequency selectivity when the NFC antenna is operating in wireless fidelity (WiFi) signal frequency.

16. The apparatus in claim 11, wherein the fractal slot includes a width of one (1) millimeter.

17. The apparatus in claim 11, wherein the fractal slots are tiled to define an area in the conductive coating, the area covers approximate extent of electromagnetic fields that induce Eddy current to the conductive coating.

18. The apparatus in claim 11, wherein the no-self loop fractal space filling curve shape includes a Hilbert Curve, a Peano Curve, a Lebesque Curve, or an H-tree curve.

19. The apparatus in claim 11, wherein the no-self loop fractal space filling curve shape includes a continuous slot line to define the fractal slot.

20. The apparatus in claim 11, wherein the no-self loop fractal space filling curve shape includes a geometric pattern configured to cut continuity of a smaller scale Eddy current, the geometric pattern is defined by a transformation function that is re-generated to model an area defined by approximate extent of electromagnetic fields that induce larger scale Eddy current.

21. A method of reducing induced currents in a apparatus chassis comprising:

providing a fractal slot to include a no-self loop fractal space filling curve shape, the fractal slot is tiled with another fractal slot to cover an area defined at least by outside loop of a near field communications (NFC) antenna that is integrated underneath the fractal slots;

radiating an electromagnetic field by the NFC antenna; and

providing high impedance to currents induced by the electromagnetic field.

22. The method in claim 21, wherein the fractal slot is constructed on a metallic chassis or carbon-fiber chassis.

23. The method in claim 21, wherein the fractal slot includes a continuous slot line to define slices in the at least one fractal slot.

24. The method in claim 21, wherein the fractal slot includes a geometric pattern configured to cut continuity of a smaller scale induced current, the geometric pattern is defined by a transformation function that is re-generated to model an area defined by approximate extent of the electromagnetic field that creates larger scale induced current.

25. The method in claim 21, wherein the fractal slot includes an adjustable width to provide the high impedance to the induced currents and to provide frequency selectivity when the NFC antenna is operating in a wireless fidelity (WiFi) signal frequency.

26. The method in claim 21, wherein the fractal slot includes a width of one (1) millimeter.

27. The method in claim 21, wherein the fractal slots are constructed to extend through a conductive coating that is integrated between the fractal slots and the NFC antenna, wherein both ends of the fractal slot in the conductive coating are grounded to maintain electrostatic discharge (ESD) protection.

28. The method in claim 21, wherein the tiled fractal slots cover the area that includes approximate extent of an electromagnetic field that induces Eddy current to a conductive coating.

29. The method in claim 21, wherein the no-self loop fractal space filling curve shape includes a Hilbert Curve, a Peano Curve, a Lebesque Curve, or an H-tree curve.

30. The method in claim 21, wherein the induced current is an Eddy current that flows in opposite direction to an injected current injected in the NFC antenna.