Transmission medium having multiple cores and methods for use therewith

• US 10,541,458 B2
• Filed: 10/12/2018
• Issued: 01/21/2020
• Est. Priority Date: 05/14/2015
• Status: Active Grant

• Current Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Original Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Inventors: Henry, Paul Shala, Taylor, William Scott, Bennett, Robert, Barzegar, Farhad, Gerszberg, Irwin, Barnickel, Donald J., Willis, III, Thomas M.
• Primary Examiner(s): Tran, Khai
• Application Number:
  US16/159,244
• Publication Number:
  US 20190044210A1
• Time in Patent Office: 466 Days
• Field of Search: 375256, 375257, 356301, 333 4, 333 5, 333238
• CPC Class Codes: H01P 3/06 Coaxial lines
• CPC Class Codes: H01P 3/16 Dielectric waveguides, i.e. without a longitudinal conductor
• CPC Class Codes: H04B 2203/5425 improving S/N by matching impedance, noise reduction, gain control
• CPC Class Codes: H04B 2203/5487 cables
• CPC Class Codes: H04B 3/32 Reducing cross-talk, e.g. by compensating
• CPC Class Codes: H04B 3/54 Systems for transmission via power distribution lines
• CPC Class Codes: H04B 3/56 Circuits for coupling, blocking, or by-passing of signals

Abstract

Aspects of the subject disclosure may include, for example, a transmission medium for propagating electromagnetic waves. The transmission medium can include a plurality of cores for selectively guiding an electromagnetic wave of a plurality of electromagnetic waves longitudinally along each core, and a shell surrounding at least a portion of each core for reducing exposure of the electromagnetic wave of each core. Other embodiments are disclosed.

Claims

1. A transmission medium, comprising:

a plurality of cables bundled together in the transmission medium, each cable of the plurality of cables comprising a core;

a material surrounding at least a portion of each core of the plurality of cables, wherein each core is configured to enable an electromagnetic wave to be bound to the core rather than the material, wherein the electromagnetic wave has an electric field intensity profile that is substantially concentrated within the material, and wherein the material reduces exposure of the electromagnetic wave to an environment; and

an absorbing material coupled to the core of each cable that absorbs a portion of the electromagnetic wave to mitigate cross-talk between the plurality of cables.

2. The transmission medium of claim 1, wherein each core of the plurality of cables comprises a conductor having an insulation layer disposed between the conductor and the material.

3. The transmission medium of claim 2, wherein the insulation layer has a first dielectric constant, wherein the material has a second dielectric constant, and wherein the first dielectric constant exceeds the second dielectric constant.

4. The transmission medium of claim 2, wherein the insulation layer comprises a high density dielectric material, and wherein the material comprises a dielectric foam.

5. The transmission medium of claim 2, wherein the electromagnetic wave is bound to the insulation layer.

6. The transmission medium of claim 1, wherein the material disposed on each core of the plurality of cables is a dielectric layer.

7. The transmission medium of claim 1, wherein each core of the plurality of cables comprises an uninsulated conductor.

8. The transmission medium of claim 7, wherein the material is disposed on an outer surface of the uninsulated conductor, and wherein the electromagnetic wave has a fundamental guided wave mode bound to the uninsulated conductor.

9. The transmission medium of claim 1, wherein each core of the plurality of cables comprises a non-conducting core, wherein a first portion of fields emitted by the electromagnetic wave is confined to the non-conducting core, and wherein a second portion of the fields is confined to the material.

10. The transmission medium of claim 9, wherein the non-conducting core comprises a dielectric core.

11. The transmission medium of claim 10, wherein the dielectric core has a first dielectric constant, wherein the material has a second dielectric constant, and wherein the first dielectric constant exceeds the second dielectric constant.

12. The transmission medium of claim 1, further comprising a cover that surrounds an outer surface of the material to prevent the exposure of the electromagnetic wave, and wherein the cover comprises a dielectric material.

13. The transmission medium of claim 12, wherein each core of the plurality of cables is optically opaque, thereby restricting a propagation of light waves in each core.

14. The transmission medium of claim 1, wherein the absorbing material comprises a carbon material.

15. A method, comprising:

receiving, by a transmission medium, a plurality of signals supplied by a plurality of launchers, wherein each signal of the plurality of signals conveys different data, and wherein the transmission medium comprises a plurality of cables, each cable of the plurality of cables comprising a core, wherein each core of the plurality of cables is surrounded at least in part by a covering; and

selectively coupling, by the transmission medium, to each signal of the plurality of signals to generate a guided electromagnetic wave at each core of the plurality of cables, each guided electromagnetic wave having an electric field intensity profile that is substantially concentrated within the covering, wherein the covering of each core reduces exposure of the guided electromagnetic wave propagating at each core, wherein each core has an absorbing material that mitigates cross-talk between the plurality of cables.

16. The method of claim 15, wherein the covering comprises a dielectric foam disposed on an outer surface of each core, and wherein each core is opaque, thereby restricting a propagation of light waves in each core.

17. A transmission medium, comprising:

a plurality of cables bundled together in the transmission medium, each cable of the plurality of cables comprising a core;

a material surrounding at least a portion of each core of the plurality of cables, wherein each core is configured to enable an electromagnetic wave to be bound to the core rather than the material, wherein the electromagnetic wave has an electric field intensity profile that is substantially concentrated within the material, and wherein the material reduces exposure of the electromagnetic wave to an environment; and

an absorbing material that absorbs a portion of the electromagnetic wave to mitigate cross-talk between the plurality of cables.

18. The transmission medium of claim 17, wherein the absorbing material comprises carbon and is positioned in gaps between the plurality of cables.

19. The transmission medium of claim 17, wherein at least one core of the plurality of cables comprises a non-conducting core, wherein a first portion of fields emitted by the electromagnetic wave is confined to the non-conducting core, and wherein a second portion of the fields is confined to the material.

20. The transmission medium of claim 17, wherein each core of the plurality of cables comprises an antenna for radiating a signal.