Guided wave directional coupler and methods for use therewith

• US 10,623,057 B1
• Filed: 12/03/2018
• Issued: 04/14/2020
• Est. Priority Date: 12/03/2018
• 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: Bennett, Robert, Barzegar, Farhad, Gerszberg, Irwin, Willis, III, Thomas M., Henry, Paul Shala
• Primary Examiner(s): Torres, Juan A
• Application Number:
  US16/207,428
• Time in Patent Office: 498 Days
• Field of Search: 375257
• CPC Class Codes: H01P 1/02 Bends; Corners; Twists
• CPC Class Codes: H01P 1/264 Waveguide terminations H01P1/262 takes precedence
• CPC Class Codes: H01P 3/10 Wire waveguides, i.e. with a single solid longitudinal conductor
• CPC Class Codes: H01P 3/16 Dielectric waveguides, i.e. without a longitudinal conductor
• CPC Class Codes: H01P 5/183 at least one of the guides being a coaxial line
• CPC Class Codes: H01P 5/188 the guides being dielectric waveguides
• CPC Class Codes: H04B 2203/5441 Wireless systems or telephone
• CPC Class Codes: H04B 2203/5479 using repeaters
• CPC Class Codes: H04B 2203/5483 using coupling circuits
• CPC Class Codes: H04B 3/46 Monitoring; Testing
• CPC Class Codes: H04B 3/544 Setting up communications; Call and signalling arrangements
• CPC Class Codes: H04B 3/56 Circuits for coupling, blocking, or by-passing of signals
• CPC Class Codes: H04B 3/58 Repeater circuits

Abstract

In accordance with one or more embodiments, a directional coupler includes a first dielectric cable is configured to receive a first electromagnetic wave from the first port and to generate a second electromagnetic wave that propagates along a transmission medium in a first direction without requiring an electrical return path. A second dielectric cable is configured to couple a first portion of the second electromagnetic wave to a second port, wherein a second portion of the second electromagnetic wave continues to propagate in the first direction along the transmission medium. A third dielectric cable is configured to couple the second portion of the second electromagnetic wave to a third port and to isolate the third port from a third electromagnetic wave propagating along the transmission medium in a second direction that is opposite to the first direction.

Claims

1. A directional coupler comprising:

a first port;

a second port;

a third port;

a first dielectric cable configured to receive a first electromagnetic wave from the first port and to generate, in response to the first electromagnetic wave, a second electromagnetic wave that propagates in a first direction along a transmission medium without requiring an electrical return path;

a second dielectric cable configured to couple a first portion of the second electromagnetic wave to the second port, wherein a second portion of the second electromagnetic wave continues to propagate in the first direction along the transmission medium; and

a third dielectric cable configured to couple the second portion of the second electromagnetic wave to the third port;

wherein the second dielectric cable is further configured to receive a third electromagnetic wave from the second port and to generate, in response to the third electromagnetic wave, a fourth electromagnetic wave that propagates along the transmission medium in a second direction; and

wherein the third dielectric cable isolates the third port from the fourth electromagnetic wave and wherein the transmission medium is a bare or insulated wire.

2. The directional coupler of claim 1, wherein the first dielectric cable, the second dielectric cable and the third dielectric cable are each conductorless.

3. The directional coupler of claim 1, wherein the first dielectric cable includes:

a first unexposed dielectric core portion and a first dielectric cladding portion that surrounds the first unexposed dielectric core portion, the first unexposed dielectric core portion configured to receive the first electromagnetic wave at a first end of the first dielectric cable and to guide the first electromagnetic wave along the first unexposed dielectric core portion; and

a first exposed dielectric core portion that is not surrounded by the first dielectric cladding portion, the first exposed dielectric core portion configured to couple a first portion of the first electromagnetic wave to the transmission medium, wherein the first portion of the first electromagnetic wave coupled to the transmission medium propagates as the second electromagnetic wave along the transmission medium.

4. The directional coupler of claim 1, further comprising:

a cable termination at a second end of the first dielectric cable configured to absorb a portion of the first electromagnetic wave that fails to couple to the transmission medium.

5. The directional coupler of claim 3, wherein the first exposed dielectric core portion is bent in an arc to facilitate radiation of the first electromagnetic wave from the first exposed dielectric core portion.

6. The directional coupler of claim 3, wherein the second dielectric cable includes:

a second unexposed dielectric core portion and a second dielectric cladding portion that surrounds the second unexposed dielectric core portion; and

a second exposed dielectric core portion that is not surrounded by the second dielectric cladding portion, the second exposed dielectric core portion configured to couple the first portion of the second electromagnetic wave from the transmission medium to the second unexposed dielectric core portion, wherein the second unexposed dielectric core portion guides the first portion of the second electromagnetic wave to the second port.

7. The directional coupler of claim 5, wherein the arc has a radius of curvature that less that a minimum radius required to support guiding of the first electromagnetic wave by the first exposed dielectric core portion.

8. The directional coupler of claim 6, wherein the second exposed dielectric core portion is bent in an arc.

9. The directional coupler of claim 6, wherein the third dielectric cable includes:

a third unexposed dielectric core portion and a third dielectric cladding portion that surrounds the third unexposed dielectric core portion; and

a third exposed dielectric core portion that is not surrounded by the third dielectric cladding portion, the third exposed dielectric core portion configured to couple the second portion of the second electromagnetic wave from the transmission medium to the third unexposed dielectric core portion, wherein the third unexposed dielectric core portion guides the second portion of the second electromagnetic wave to the second port.

10. The directional coupler of claim 9, wherein the third exposed dielectric core portion is bent in an arc.

11. A method comprising:

receiving, via a first dielectric cable, a first electromagnetic wave from a first port;

generating, via the first dielectric cable and in response to the first electromagnetic wave, a second electromagnetic wave that propagates in a first direction along a transmission medium without requiring an electrical return path, wherein the transmission medium is a bare or insulated wire;

coupling, via a second dielectric cable, a first portion of the second electromagnetic wave to a second port, wherein a second portion of the second electromagnetic wave continues to propagate in the first direction along the transmission medium; and

coupling, via a third dielectric cable, the second portion of the second electromagnetic wave to a third port, wherein the third dielectric cable isolates the third port from a third electromagnetic wave propagating along the transmission medium in a second direction that is opposite to the first direction.

12. The method of claim 11, wherein the first dielectric cable, the second dielectric cable and the third dielectric cable are each conductorless.

13. The method of claim 11, wherein the first dielectric cable includes:

a first unexposed dielectric core portion and a first dielectric cladding portion that surrounds the first unexposed dielectric core portion, the first unexposed dielectric core portion configured to receive the first electromagnetic wave at a first end of the first dielectric cable and to guide the first electromagnetic wave along the first unexposed dielectric core portion; and

a first exposed dielectric core portion that is not surrounded by the first dielectric cladding portion, the first exposed dielectric core portion configured to couple a first portion of the first electromagnetic wave to the transmission medium, wherein the first portion of the first electromagnetic wave coupled to the transmission medium propagates as the second electromagnetic wave along the transmission medium.

14. The method of claim 11, further comprising:

absorbing, via a cable termination at a second end of the first dielectric cable, a portion of the first electromagnetic wave that fails to couple to the transmission medium.

15. The method of claim 13, wherein the first exposed dielectric core portion is bent in an arc to facilitate radiation of the first electromagnetic wave from the first exposed dielectric core portion.

16. The method of claim 13, wherein the second dielectric cable includes:

a second unexposed dielectric core portion and a second dielectric cladding portion that surrounds the second unexposed dielectric core portion; and

a second exposed dielectric core portion that is not surrounded by the second dielectric cladding portion, the second exposed dielectric core portion configured to couple the first portion of the second electromagnetic wave from the transmission medium to the second unexposed dielectric core portion, wherein the second unexposed dielectric core portion guides the first portion of the second electromagnetic wave to the second port.

17. The method of claim 15, wherein the arc has a radius of curvature that less that a minimum radius required to support guiding of the first electromagnetic wave by the first exposed dielectric core portion.

18. The method of claim 16, wherein the second exposed dielectric core portion is bent in an arc.

19. The method of claim 16, wherein the third dielectric cable includes:

a third unexposed dielectric core portion and a third dielectric cladding portion that surrounds the third unexposed dielectric core portion; and

a third exposed dielectric core portion that is not surrounded by the third dielectric cladding portion, the third exposed dielectric core portion configured to couple the second portion of the second electromagnetic wave from the transmission medium to the third unexposed dielectric core portion, wherein the third unexposed dielectric core portion guides the second portion of the second electromagnetic wave to the second port.

20. A directional coupler comprising:

means for receiving a first electromagnetic wave from a first port;

means for generating, in response to the first electromagnetic wave, a second electromagnetic wave that propagates in a first direction along a transmission medium without requiring an electrical return path, wherein the transmission medium is a bare or insulated wire;

means for coupling a first portion of the second electromagnetic wave to a second port, wherein a second portion of the second electromagnetic wave continues to propagate in the first direction along the transmission medium;

means for coupling the second portion of the second electromagnetic wave to a third port; and

means for isolating the third port from a third electromagnetic wave propagating along the transmission medium in a second direction that is opposite to the first direction.