Method for detecting bridged taps on telephony cable

• US 20050243904A1
• Filed: 05/03/2004
• Published: 11/03/2005
• Est. Priority Date: 05/03/2004
• Status: Active Grant

• Current Assignee: SBC Knowledge Ventures LP (AT&T, Inc.)
• Original Assignee: SBC Knowledge Ventures LP (AT&T, Inc.)
• Inventors: Savoor, Raghvendra G., Hart, Richard Dennis, Shrikhande, Kapil, Cambron, George Keith, King, Laurie G.
• Granted Patent: US 7,388,906 B2
• Time in Patent Office: Days
• US Class Current: 375/222
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways
• CPC Class Codes: H04M 3/085 Fault locating arrangements
• CPC Class Codes: H04M 3/2209 for lines also used for data transmission
• CPC Class Codes: H04M 3/30 for subscriber's lines , for the local loop

Abstract

In a particular embodiment a method of collecting and processing modem data is provided. The method includes,during training of a broadband modem, sending a series of tones within a frequency transmission band of the broadband modem, receiving the transmitted series of tones at a receiving broadband modem, receiving a measurement value of a power level for each of the received tones in the series of tones transmitted to the receiving broadband modem, determining a transmission loss for each of the series of tones by comparing the predetermined transmission power level, and the received measured power level, performing a statistical match comparison between each of the received tone signals and a plurality of different computer models of a single transmission facility having various bridge taps connected to the single transmission facility, and determining a best fit between each of the received tone signals and one of the plurality of the bridge tap computer models. The series of tones have a predetermined transmission power level.

Claims

1. A method of collecting and processing modem data, the method comprising:

during training of a broadband modem, sending a series of tones within a frequency transmission band of the broadband modem, the series of tones having a predetermined transmission power level;

receiving the transmitted series of tones at a receiving broadband modem;

receiving a measurement value of a power level for each of the received tones in the series of tones transmitted to the receiving broadband modem;

determining a transmission loss for each of the series of tones by comparing the predetermined transmission power level and the received measured power level;

performing a statistical match comparison between each of the received tone signals and a plurality of different computer models of a single transmission facility having various bridged taps connected to the single transmission facility; and

determining a best fit between each of the received tone signals and at least one of the plurality of the bridged tap computer models.

2. The method of claim 1, further comprising, based on the computer model having the best fit, communicating bridged tap information related to the computer model.

3. The method of claim 2, further comprising taking a network operations action based on the bridged tap information.

4. The method of claim 1, wherein the bridged tap information includes the number and type of bridged taps, and tap lengths.

5. The method of claim 4, wherein the tap information further comprises an effect of the taps on communications service, and a probability that the information is accurate with respect to the physical communication line coupled to the receiving broadband modem.

6. A method of estimating taps coupled to a communication line connected to a broadband modem device, the method comprising:

during a training session of the broadband modem device, receiving a plurality of tones communicated over the communication line to the broadband modem device, the plurality of tones within a frequency reception band of the broadband modem, the plurality of tones having a predetermined transmission power level;

measuring a power level for each of the plurality of received tones;

determining a transmission loss for each of the plurality of tones by comparing the predetermined transmission power level and the measured power level for each of the plurality of tones; and

performing statistical match comparisons between each of the plurality of received tones and a plurality of computer models, wherein each of the plurality of computer models represents electrical transmission properties of a single transmission facility coupled to at least one tap.

7. The method of claim 6, further comprising determining a best fit between each of the plurality of received tones and one of the plurality of the tap computer models based on the statistical match comparisons.

8. The method of claim 6, wherein a first of the plurality of computer models identifies a first tap having a first tap length and a second of the plurality of computer models identifies a second bridge tap having a second bridge tap length.

9. The method of claim 8, wherein the first tap length is longer than the second tap length.

10. The method of claim 9, wherein the first tap length is greater than 500 feet and the second tap length is less than 500 feet.

11. The method of claim 10, further comprising removing a first physical tap from the communication line wherein the first physical tap is represented by the first tap of the tap computer model, but wherein a second physical tap of the communication line is not removed, the second physical tap represented by the second tap of the bridge tap computer model.

12. The method of claim 6, further comprising communicating the tap information from the broadband modem device to a storage facility that is remote from the broadband modem device.

13. The method of claim 12, wherein the storage facility is a computer server accessible to a computer network.

14. The method of claim 12, wherein the storage facility is a computer workstation providing access to a user interface of a network management user.

15. The method of claim 14, further comprising performing computer analysis of tap information derived from one of the plurality of computer models, the analysis of the bridge information to prepare and present user information via the user interface to the network management user.

16. The method of claim 12, wherein the storage facility is a computer server operated by a manufacturer of the broadband modem device.

17. The method of claim 14, wherein the computer workstation receives an FTP file that includes the tap information in response to making an FTP request via a distributed computer network.

18. The method of claim 6, wherein the broadband modem device is a digital subscriber line (DSL) modem and wherein each of the plurality of tones corresponds to a DMT center frequency according to a DSL standard.

19. A data communication system comprising:

a memory including logic to estimate bridged taps coupled to a communication line that is coupled to an input of the data communication modem, the logic comprising;

a data receiving module configured to capture data corresponding to a plurality of tones communicated over the communication line during a modem training session, the plurality of tones within a frequency reception band of the data communication modem, each of the plurality of tones having a predetermined transmission power level;

a measurement module to capture measurement data related to a measured power level for each of the plurality of received tones;

an insertion loss routine to determine a transmission loss for each of the plurality of tones by comparing the predetermined transmission power level and the measurement data for each of the plurality of tones; and

statistical matching logic configured to perform statistical match comparisons between the captured data corresponding to each of the received tone signals and a plurality of computer models, each of the plurality of computer models representing electrical transmission properties of a single transmission facility coupled to at least one bridged tap.

20. The system of claim 19, further comprising a tap analysis module, bridge tap analysis module to perform an analysis on a computer model determined to be a best fit match to the captured data corresponding to each of the received tone signals and to generate presentation level bridged tap data to be communicated to a user interface.

21. The system of claim 20, wherein the presentation level bridged tap data comprises a number of bridged taps, bridged tap lengths, effect on service, and an estimate of accuracy of the computer model.

22. The system of claim 19, wherein the memory is embedded within a broadband data modem.

23. The system of claim 19, wherein the memory is within a computer workstation that is remote from a broadband data modem that receives the plurality of tones.

24. The system of claim 19, wherein the memory is within a computer workstation coupled to a central telephone office, the central telephone office including broadband communication equipment that supports a network modem coupled to the communication line.

25. A method of estimating taps coupled to a communication line connected to a broadband modem device, the method comprising:

during a training session of the broadband modem device, receiving a plurality of tones communicated over the communication line to the broadband modem device, the plurality of tones within a frequency reception band of the broadband modem, the plurality of tones having a predetermined transmission power level;

measuring a power level for each of the plurality of received tones;

determining a transmission loss for each of the plurality of tones by comparing the predetermined transmission power level and the measured power level for each of the plurality of tones;

performing statistical match comparisons between each of the plurality of received tones and a plurality of computer models, wherein each of the plurality of computer models represents electrical transmission properties of a single transmission facility coupled to at least one tap; and

adding a second tap to the computer models and based on an insertion loss increase, determining the distance between the at least one tap and the second tap.