Echo canceler-based mechanism for performing and reporting fault diagnostic testing of repeatered telecommunication line

• US 7,174,488 B1
• Filed: 04/28/2003
• Issued: 02/06/2007
• Est. Priority Date: 09/18/2002
• Status: Active Grant

• Current Assignee: ADTRAN Incorporated (ADTRAN Holdings, Inc.)
• Original Assignee: ADTRAN Incorporated (ADTRAN Holdings, Inc.)
• Inventors: Chu, Fred T.
• Primary Examiner(s): Kerveros; James C
• Application Number:
  US10/424,304
• Time in Patent Office: 1,380 Days
• Field of Search: 714/712, 714/713, 714/714, 714/716
• US Class Current: 714/712
• CPC Class Codes: H04M 3/085 Fault locating arrangements

Abstract

A repeater-installed fault location mechanism conducts parametric measurements on a segment of wireline to which the repeater is connected, and adjusts taps of an echo cancellation operator in the repeater transceiver equipment, in accordance with the response of the wireline to an electrical stimulus imparted to the wireline segment. Information representative of the echo canceler tap coefficients is then transmitted over an overhead to a processor, to determine fault the location of a fault.

Claims

1. A method of determining the location of a fault along a repeatered wireline serving digital subscriber equipment at a location remote with respect to a central office facility, said method comprising the steps of:

(a) applying an electrical stimulus to an electrically conductive wireline pair from a repeater installed in said wireline pair;

(b) at said repeater, measuring a response of said electrically conductive wireline pair to said electrical stimulus applied in step (a), and generating an output from which the distance from said repeater to said fault is to be determined; and

(c) processing said output generated in step (b) to determine where in said electrically conductive wireline pair said fault is located.

2. The method according to claim 1, wherein step (b) comprises transporting a message containing information representative of said output over an overhead channel from said repeater to said central office facility.

3. The method according to claim 2, wherein step (c) comprises processing said information to derive a measure of distance from said repeater to said fault.

4. The method according to claim 2, wherein step (c) comprises processing information contained in said message at a said central office facility to determine in the location of said fault.

5. The method according to claim 2, wherein step (c) comprises processing information contained in said message at a location separate from said central office facility to determine the location of said fault.

6. The method according to claim 1, wherein step (b) comprises establishing attributes of a digital echo canceler in said repeater, and step (c) comprises analyzing attributes of said digital echo canceler to derive a measure of the location of said fault.

7. The method according to claim 1, wherein said fault comprises an open circuit.

8. The method according to claim 1, wherein said fault comprises a short circuit.

9. The method according to claim 1, wherein step (a) comprises receiving a digital data signal, generating said electrical stimulus representative of said digital data signal, and applying said electrical stimulus to said electrically conductive wireline pair from said repeater installed in said electrically conductive wireline pair.

10. A method of determining the location of a fault along a repeatered wireline serving digital subscriber equipment at a location remote with respect to a central office facility, said method comprising the steps of:

(a) applying an electrical stimulus to a wireline segment from a repeater installed in said wireline;

(b) at said repeater, measuring a response of said wireline segment to said electrical stimulus applied in step (a), and generating an output from which the distance from said repeater to said fault is to be determined; and

(c) processing said output generated in step (b) to determine where in said wireline segment said fault is located wherein step (a) comprises applying a wideband signal to said wireline segment from said repeater, and step (b) comprises generating coefficients of an echo cancellation operator in accordance with the measured reflection response of said wireline segment to said wideband signal, and generating an output representative of said coefficients of said echo cancellation operator.

11. An arrangement for determining the location of a fault along a repeatered electrically conductive wireline pair serving digital subscriber equipment at a location remote with respect to a central office facility, comprising:

an electrical stimulus generator within a repeater; and

a measurement unit installed in said repeater, which is operative to measure a response to said electrical stimulus of an electrically conductive wireline pair to which said repeater is connected, and to transmit a message over an overhead to said central office representative of said response.

12. The arrangement according to 11, further including a processing unit that is operative to process information contained in said message transmitted over said overhead from said repeater to determine where in said electrically conductive wireline pair said fault is located.

13. The arrangement according to claim 12, wherein said processing unit is operative to process said information to derive a measure of distance from said repeater to said fault.

14. The arrangement according to claim 12, wherein said processor is operative to process information contained in said message at a said central office facility to determine in the location of said fault.

15. The arrangement according to claim 12, wherein said processor is operative to process information contained in said message at a location separate from said central office facility to determine the location of said fault.

16. The arrangement according to claim 12, wherein said measurement unit is operative to establish attributes of a digital echo canceler in said repeater, and said processing unit is operative to analyze attributes of said digital echo canceler to derive a measure of the location of said fault.

17. The arrangement according to claim 11, wherein said fault comprises an open circuit.

18. The arrangement according to claim 11 wherein said fault comprises a short circuit.

19. The arrangement according to claim 11, wherein said electrical stimulus generator is operative to receive a digital data signal, generate an electrical stimulus representative of said digital data signal, and apply said electrical stimulus to said electrically conductive wireline pair from said repeater.

20. An arrangement for determining the location of a fault along a repeatered wireline serving digital subscriber equipment at a location remote with respect to a central office facility, comprising:

a measurement unit installed in said repeater, which is operative to measure a response to said electrical stimulus of a wireline segment to which said repeater is connected, and to transmit a message over an overhead to said central office representative of said response; and

a processing unit that is operative to process information contained in said message transmitted over said overhead from said repeater to determine where in said wireline segment said fault is located, and wherein said an electrical stimulus generator is operative to apply a wideband signal to said wireline segment from said repeater, and said measurement unit is operative to generate coefficients of an echo cancellation operator in accordance with the measured reflection response of said wireline segment to said wideband signal, and to generate an output representative of said coefficients of said echo cancellation operator.

21. A method comprising;

(a) conducting electrical measurements upon an electrically conductive wireline pair from a repeater unit installed in said electrically conductive wireline pair;

(b) reporting results of said electrical measurements conducted in step (a) over an orderwire to a processing unit; and

(c) processing said results of said electrical measurements reported in step (b) at said processing unit to determine the location of said fault.

22. The method according to claim 21, wherein step (a) comprises stimulating said electrically conductive wireline pair to establish attributes of a digital echo canceler, step (b) comprises transmitting information representative of said attributes of said digital echo canceller to said processing unit, and step (c) comprises analyzing said attributes of said digital echo canceler to derive a measure of distance from said DSL line card to said fault.

23. The method according to claim 21, wherein step (a) comprises conducting said electrical measurements upon said electrically conductive wireline pair by receiving a digital data signal, generating an electrical stimulus representative of said digital data signal, and applying said electric stimulus to said electrically conductive wireline pair from said repeater unit.