System and method for detecting anomalies along telecommunication lines

• US 8,767,921 B2
• Filed: 07/11/2012
• Issued: 07/01/2014
• Est. Priority Date: 12/04/2003
• Status: Expired due to Term

• Current Assignee: ADTRAN Incorporated (ADTRAN Holdings, Inc.)
• Original Assignee: ADTRAN Incorporated (ADTRAN Holdings, Inc.)
• Inventors: Hunt, Gary, Chu, Fred, Gusler, Lee T. Jr.
• Primary Examiner(s): Jamal, Alexander
• Application Number:
  US13/546,417
• Publication Number:
  US 20120281818A1
• Time in Patent Office: 720 Days
• Field of Search: 379/406.01, 379/22.03
• US Class Current: 379/22.03
• CPC Class Codes: H04B 3/238 using initial training sequence
• CPC Class Codes: H04M 3/002 Applications of echo suppressors or cancellers in telephonic connections in two-way loud-speaking telephone systems H04M9/08, echo suppressors or cancellers per se H04B3/20
• CPC Class Codes: H04M 3/085 Fault locating arrangements
• CPC Class Codes: H04M 3/28 Automatic routine testing ; Fault testing; Installation testing; Test methods, test equipment or test arrangements therefor

Abstract

An anomaly detection system comprises an echo canceler and anomaly detection logic. The echo canceler has a plurality of taps respectively associated with a plurality of tap coefficients. The anomaly detection logic is configured to determine a difference between a new tap coefficient associated with one of the taps and a previous tap coefficient associated with the one tap. The anomaly detection logic is configured to perform a comparison between the difference and a threshold and to detect an anomaly along a telecommunication line based on the comparison.

Claims

1. An anomaly detection system, comprising:

a telecommunication line having a plurality of wires including at least a first wire joined to a second wire, the telecommunication line having a time varying anomaly at a junction of the first wire and the second wire, the time varying anomaly causing a transmission characteristic of the telecommunication line to fluctuate at the junction;

a transmitter coupled to the telecommunication line; and

anomaly detection logic configured to detect the anomaly based on signals communicated across the telecommunication line, the anomaly detection logic further configured to indicate a location of the detected anomaly along the telecommunication line.

2. The system of claim 1, wherein the transmitter is configured to transmit signals across the telecommunication line, and wherein the anomaly detection logic is configured to detect the anomaly based on echoes of the signals.

3. The system of claim 1, further comprising logic configured to maintain tap coefficients based on the signals, wherein the anomaly detection logic is configured to detect the anomaly based on the tap coefficients.

4. The system of claim 3, wherein each of the tap coefficients is indicative of an impedance of the junction at a different moment in time, wherein the anomaly detection logic is configured to compare each of the tap coefficients to at least one baseline coefficient, and wherein the anomaly detection logic is configured to determine a value based on each comparison and to detect the anomaly based on the value.

5. The system of claim 4, wherein the anomaly detection logic is configured to determine the tap coefficients during data communication between the transmitter and a remote receiver coupled to the transmitter via the telecommunication line.

6. The system of claim 3, wherein the anomaly detection logic is configured to determine the tap coefficients during data communication between the transmitter and a remote receiver coupled to the transmitter via the telecommunication line.

7. The system of claim 1, wherein the signals are communicated across the telecommunication line during data communication between the transmitter and a remote receiver coupled to the transmitter via the telecommunication line.

8. The system of claim 1, further comprising an echo canceler configured to cancel, based on a plurality of tap coefficients, echoes of signals transmitted by the transmitter across the telecommunication line, the echo canceler configured to adjust the tap coefficients based on the echoes, wherein the anomaly detection logic is configured to detect the anomaly based on the tap coefficients.

9. The system of claim 1, wherein the signals are transmitted by the transmitter across the telecommunication line and are received by a remote receiver from the telecommunication line.

10. The system of claim 1, further comprising logic configured to store tap coefficients and to adjust the tap coefficients based on signals communicated across the telecommunication line, wherein the anomaly detection logic is configured to detect the anomaly based on the tap coefficients.

24. The system of claim 3, wherein each of the tap coefficients corresponds to a respective point along the telecommunication line, wherein the anomaly detection logic is configured to compare changes in one of the tap coefficients to changes in other tap coefficients for determining whether an anomaly exists at the point along the telecommunication line corresponding to the one tap coefficient.

11. An anomaly detection system, comprising:

a telecommunication line having a plurality of wires including at least a first wire joined to a second wire, the telecommunication line having a time varying anomaly at a junction of the first wire and the second wire, the time varying anomaly causing a resistance of the telecommunication line at the junction to fluctuate;

a first transceiver coupled to the telecommunication line and configured to communicate with a second transceiver via the telecommunication line; and

anomaly detection logic configured to detect the anomaly based on signals communicated from the first transceiver to the second transceiver.

12. The system of claim 11, further comprising logic configured to maintain tap coefficients based on the signals, wherein the anomaly detection logic is configured to detect the anomaly based on the tap coefficients.

13. The system of claim 12, wherein each of the tap coefficients is indicative of the resistance at the junction at a different moment in time, wherein the anomaly detection logic is configured to compare each of the tap coefficients to at least one baseline coefficient, and wherein the anomaly detection logic is configured to determine a value based on each comparison and to detect the anomaly based on the value.

14. The system of claim 11, further comprising an echo canceler configured to cancel echoes of the signals based on a plurality of tap coefficients, the echo canceler configured to adjust the tap coefficients based on the echoes, wherein the anomaly detection logic is configured to detect the anomaly based on the tap coefficients.

15. The system of claim 11, further comprising logic configured to store tap coefficients based on the signals and to adjust the tap coefficients based on the signals, wherein the anomaly detection logic is configured to detect the anomaly based on the tap coefficients.

25. The system of claim 12, wherein each of the tap coefficients corresponds to a respective point along the telecommunication line, wherein the anomaly detection logic is configured to determine a value indicative of an amount that the one tap coefficient changes over time relative to changes in other tap coefficients, and wherein the anomaly detection logic is configured to detect the anomaly based on the value.

16. An anomaly detection method, comprising the steps of:

communicating signals across a telecommunication line, the telecommunication line having a plurality of wires including at least a first wire joined to a second wire, the telecommunication line further having a time varying anomaly at a junction of the first wire and the second wire, the time varying anomaly causing a resistance of the telecommunication line at the junction to fluctuate;

automatically detecting the anomaly based on the signals; and

indicating a location of the detected anomaly.

17. The method of claim 16, wherein the detecting step is based on echoes of the signals.

18. The method of claim 16, further comprising the step of maintaining tap coefficients based on the signals, wherein the detecting step is based on the tap coefficients.

19. The method of claim 16, further comprising the steps of:

canceling echoes of the signals based on a plurality of tap coefficients; and

adjusting the tap coefficients based on the echoes, wherein the detecting step is based on the tap coefficients.

20. The method of claim 16, further comprising the steps of:

storing tap coefficients; and

updating the tap coefficients based on the signals, wherein the detecting step is based on the tap coefficients.

21. The method of claim 16, further comprising the steps of:

comparing a first tap coefficient to at least one baseline coefficient, the first tap coefficient indicative of an impedance at the junction during a first time period;

updating the first tap coefficient thereby forming an updated tap coefficient indicative of an impedance at the junction during a second time period;

comparing the updated tap coefficient to the at least one baseline coefficient; and

determining a value based on each of the comparing steps, wherein the detecting step is based on the value.

22. The method of claim 21, wherein the at least one baseline coefficient includes a first baseline coefficient and a second baseline coefficient, wherein the comparing the first tap coefficient to the at least one baseline coefficient step comprises the step of comparing the first tap coefficient to the first baseline coefficient, wherein the method further comprises the step of updating the first baseline coefficient thereby forming the second baseline coefficient, and wherein the comparing the updated tap coefficient step comprises the step of comparing the updated tap coefficient to the second baseline coefficient.

23. The method of claim 18, wherein each of the tap coefficients corresponds to a respective point along the telecommunication line, and wherein the method further comprises the step of comparing changes in one of the tap coefficients to changes in other tap coefficients, wherein the detecting step is based on the comparing step.