Guided wave communication system with interference cancellation and methods for use therewith

• US 10,530,403 B2
• Filed: 04/16/2019
• Issued: 01/07/2020
• Est. Priority Date: 11/09/2017
• 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: Willis, III, Thomas M., Vannucci, Giovanni, Henry, Paul Shala
• Primary Examiner(s): Tran, Pablo N
• Application Number:
  US16/385,266
• Publication Number:
  US 20190245567A1
• Time in Patent Office: 266 Days
• CPC Class Codes: H04B 1/0475 with means for limiting noise, interference or distortion H04B1/0483 takes precedence
• CPC Class Codes: H04B 1/40 Circuits
• CPC Class Codes: H04B 3/32 Reducing cross-talk, e.g. by compensating
• CPC Class Codes: H04B 3/46 Monitoring; Testing
• CPC Class Codes: H04B 3/52 Systems for transmission between fixed stations via waveguides
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition

Abstract

In accordance with one or more embodiments, a transmission device includes a receiver configured to receive an interfering signal via an antenna. A transmitter is configured to generate first electromagnetic signals conveying first data. A coupler is configured to generate first guided electromagnetic waves in response to combined electromagnetic signals, wherein the first guided electromagnetic waves propagate, without requiring an electrical return path, along a surface of a transmission medium of a distributed antenna system. A cancellation circuit is configured to generate the combined electromagnetic signals, based on the interfering signal and the first electromagnetic signals, wherein the combined electromagnetic signals mitigate interference by the interfering signal with the first guided electromagnetic waves.

Claims

1. A transmission device comprising:

a first receiver configured to receive an interfering signal via an antenna;

a coupler configured to generate first guided electromagnetic waves in response to combined electromagnetic signals, wherein the first guided electromagnetic waves propagate, without requiring an electrical return path, along a surface of a transmission medium of a distributed antenna system; and

a cancellation circuit configured to generate the combined electromagnetic signals, based on the interfering signal and first electromagnetic signals conveying first data from a transmitter, wherein the combined electromagnetic signals cancel at least a portion of the interfering signal from the first guided electromagnetic waves.

2. The transmission device of claim 1, wherein the interfering signal corresponds to a transmission by a mobile device to a base station.

3. The transmission device of claim 1, wherein the cancellation circuit includes:

an adjustment circuit configured to generate an adjusted interfering signal by adjusting an amplitude and a phase of the interfering signal; and

a combining circuit configured to generate the combined electromagnetic signal by combining the first electromagnetic signals with the adjusted interfering signal.

4. The transmission device of claim 3, wherein the combining includes a subtraction of the adjusted interfering signal from the first electromagnetic signals or an addition of the adjusted interfering signal to the first electromagnetic signals.

5. The transmission device of claim 3, further comprising:

a second receiver configured to extract second data from second electromagnetic signals generated by the coupler in response to second guided electromagnetic waves received from another transmission device coupled to the transmission medium; and

wherein the cancellation circuit further includes a controller configured to control the adjusting of the amplitude and the phase of the interfering signal, based on feedback received via the second data.

6. The transmission device of claim 1, wherein the interfering signal corresponds to a transmission by a first mobile device to a first base station and wherein the distributed antenna system is coupled to a second base station.

7. The transmission device of claim 6, wherein the first receiver and the antenna are further configured to facilitate communications between a second mobile device and the second base station via the distributed antenna system.

8. The transmission device of claim 1, wherein the first guided electromagnetic waves are directed to another transmission device of the distributed antenna system, and wherein the another transmission device is configured to receive at least a portion of the first guided electromagnetic waves via the transmission medium.

9. The transmission device of claim 1, wherein the transmission medium is a bare or insulated wire.

10. The transmission device of claim 1, wherein the first guided electromagnetic waves have a microwave frequency band and wherein the interfering signal has a frequency in a fourth-generation wireless frequency band.

11. A method comprising:

receiving an interfering signal via an antenna;

generating combined electromagnetic signals, based on the interfering signal and first electromagnetic signals conveying first data; and

generating first guided electromagnetic waves in response to the combined electromagnetic signals, wherein the first guided electromagnetic waves propagate, without requiring an electrical return path, along a surface of a transmission medium of a distributed antenna system;

wherein the combined electromagnetic signals cancel at least a portion of the interfering signal from the first guided electromagnetic waves.

12. The method of claim 11, wherein the interfering signal corresponds to a transmission by a mobile device to a base station.

13. The method of claim 11, wherein generating the combined electromagnetic signals includes:

generating an adjusted interfering signal by adjusting an amplitude and a phase of the interfering signal; and

generating the combined electromagnetic signal by combining the first electromagnetic signals with the adjusted interfering signal.

14. The method of claim 13, wherein the combining includes a subtraction of the adjusted interfering signal from the first electromagnetic signal or an addition of the adjusted interfering signal to the first electromagnetic signals.

15. The method of claim 13, further comprising:

receiving second data in response to second guided electromagnetic waves received from another transmission device coupled to the transmission medium;

wherein the generating the adjusted interfering signal is based on feedback received via the second data.

16. The method of claim 11, further comprising:

receiving communication signals conveying the first data from a first base station;

wherein the generating the first electromagnetic signals is responsive to the communication signals; and

wherein the interfering signal corresponds to a transmission by a first mobile device to a second base station.

17. The method of claim 16, further comprising:

facilitating communications between a second mobile device and the first base station via the antenna.

18. The method of claim 11, wherein the first guided electromagnetic waves are directed to a transmission device of a distributed antenna system, and wherein the transmission device is configured to receive at least a portion of the first guided electromagnetic waves via the transmission medium.

19. The method of claim 11, wherein the transmission medium is a bare or insulated wire.

20. A transmission device comprising:

means for wirelessly receiving an interfering signal via an antenna;

means for generating combined electromagnetic signals, based on the interfering signal and electromagnetic signals conveying data; and

means for generating guided electromagnetic waves in response to the combined electromagnetic signals, wherein the guided electromagnetic waves propagate, without requiring an electrical return path, along a surface of a transmission medium of a distributed antenna system;

wherein the combined electromagnetic signals cancel at least a portion of the interfering signal from the guided electromagnetic waves.