Launch topology for field confined near field communication system

• US 10,461,810 B2
• Filed: 06/29/2017
• Issued: 10/29/2019
• Est. Priority Date: 06/29/2017
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Cook, Benjamin Stassen, Brooks, Nathan, Sankaran, Swaminathan, Kramer, Bradley Allen, Morgan, Mark W., Haroun, Baher
• Primary Examiner(s): Trinh, Sonny
• Application Number:
  US15/638,212
• Publication Number:
  US 20190007101A1
• Time in Patent Office: 852 Days
• Field of Search: 455 411
• CPC Class Codes: G06K 7/10237 the reader and the record carrier being capable of selectively switching between reader and record carrier appearance, e.g. in near field communication [NFC] devices where the NFC device may function as an RFID reader or as an RFID tag
• CPC Class Codes: H01Q 1/3283 side-mounted antennas, e.g. bumper-mounted, door-mounted mounted on windscreens H01Q1/1271
• 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: H04B 5/24 Inductive coupling
• CPC Class Codes: H04B 5/72 for local intradevice communication
• CPC Class Codes: H04W 4/80 Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication

Abstract

A system is provided in which a set of modules each have a substrate on which is mounted a radio frequency (RF) transmitter and/or an RF receiver coupled to a near field communication (NFC) coupler located on the substrate. Each module has a housing that surrounds and encloses the substrate. The housing has a port region on a surface of the housing. Each module has a field confiner located between the NFC coupler and the port region on the housing configured to guide electromagnetic energy emanated from the NFC coupler through the port region to a port region of an adjacent module. A reflective surface is positioned adjacent the backside of each NFC coupler to reflect back side electromagnetic towards the port region.

Claims

1. A system comprising a module, the module comprising:

a substrate;

a radio frequency (RF) transmitter mounted on the substrate;

a near field communication (NFC) coupler, on the substrate, coupled to the RF transmitter, wherein the NFC coupler has a front side and a back side, and wherein the NFC coupler comprises an antenna, comprising;

an outer conductive region; and

a non-conducting slot surrounded by the outer conductive region;

a housing that surrounds the substrate, the housing having a port region;

a field confiner, between the front side of the NFC coupler and the port region of the housing, arranged to propagate a first portion of near-field electromagnetic energy through the port region, the near-field electromagnetic energy being emanated from the NFC coupler; and

a reflective surface, facing the back side of the NFC coupler, arranged to reflect a second portion of the near-field electromagnetic energy towards the port region.

2. The system of claim 1, the RF transmitter configured to generate an RF signal having a frequency, wherein the reflective surface is an artificial magnetic conductor (AMC) surface configured to reflect near-field electromagnetic energy having the frequency of the RF signal with approximately zero phase shift.

3. The system of claim 2, the AMC surface comprising a first conductive layer and a second conductive layer, separated by a dielectric layer, wherein the first conductive layer is an array of isolated conductive regions, and the second conductive layer is coupled to a ground reference for the RF transmitter.

4. The system of claim 3, in which the AMC surface is in a second substrate that is separate from the substrate.

5. The system of claim 3, the module further comprising:

a second RF transmitter, mounted on the substrate, coupled to a second NFC coupler located on the substrate, wherein the second NFC coupler has a front side and a back side;

a second AMC surface proximate to the back side of the second NFC coupler; and

a second field confiner proximate to the front side of the second NFC coupler, the second field confiner configured to evanescently couple near-field electromagnetic energy to an RF receiver.

6. The system of claim 5, the second AMC surface comprising a first conductive layer and a second conductive layer, separated by a dielectric layer, wherein the first conductive layer is an array of isolated conductive regions, and the second conductive layer is coupled to a ground reference for the RF receiver.

7. The system of claim 6, wherein the second conductive layer of the AMC surface and the second conductive layer of the second AMC surface are the same layer.

8. The system of claim 2, further comprising a plurality of NFC couplers coupled to a plurality of RF transmitters or receivers mounted on the substrate, wherein each of the plurality of NFC couplers is proximate to the AMC surface.

9. The system of claim 1, further comprising:

a backplane;

a plurality of modules attached to the backplane, each module of the plurality of modules having a first port region and a second port region; and

wherein first port regions of each module aligns with the second port region of an adjacent module.

10. The system of claim 1, wherein the field confiner fills a gap between the port region of the housing and the front side of the NFC coupler.

11. The system of claim 1, wherein the port region of the housing is offset laterally from the NFC coupler, wherein the field confiner is skewed to fill a gap between the port region of the housing and the front side of the NFC coupler.

12. The system of claim 1, wherein the field confiner is a dielectric block having a relative permittivity greater than 1.0.

13. The system of claim 1, wherein the field confiner is a negative index metamaterial.

14. The system of claim 1, wherein an electromagnetic field emanated from the NFC coupler has a frequency of 10-30 GHz.

15. The system of claim 1, wherein the field confiner has a conductive sidewall.

16. The system of claim 1, wherein the antenna further comprises an inner conductive region within the non-conducting slot.

17. The system of claim 16, wherein the inner conductive region is circular.

18. The system of claim 1, wherein the non-conducting slot is rectangular.

19. A method for transmitting a signal between modules in a system, the method comprising:

generating, by a radio frequency (RF) transmitter of a module, an RF electromagnetic field;

emanating the RF electromagnetic field, by a near field communication (NFC) coupler of the module, wherein the NFC coupler comprises an antenna, comprising;

an outer conductive region; and

a non-conducting slot surrounded by the outer conductive region;

reflecting, by a reflective surface of the module, a first portion of the RF electromagnetic field; and

confining and directing a second portion the RF electromagnetic field, by a field confiner of the module to a port region of the module.

20. A module comprising:

a substrate;

a radio frequency (RF) transmitter mounted on the substrate;

a near field communication (NFC) coupler, on the substrate, coupled to the RF transmitter, wherein the NFC coupler has a front side and a back side, and wherein the NFC coupler comprises an antenna comprising a conductor having a fractal pattern that includes a plurality of conductor shapes having corners and edge surfaces extending from the corners, wherein the plurality of conductor shapes are coupled to each other at the corners and separated from each other along the edge surfaces;

a housing surrounding and enclosing the substrate, the housing having a port region;

a field confiner, between the front side of the NFC coupler and the port region, arranged to propagate a first portion of near-field electromagnetic energy through the port region, the near-field electromagnetic energy being emanated from the NFC coupler; and

a reflective surface, facing the back side of the NFC coupler, arranged to reflect a second portion of the near-field electromagnetic energy towards the port region.