Granted Patent B2

US 9,391,834 · App. 14/384,368 · Granted Jul 12, 2016

Abstract

Claims (109)

1. A method comprising:

injecting differential mode signal probes onto two conductors of a Digital Subscriber Line (DSL line);

measuring a common-mode rejection ratio (CMRR) of the differential mode signal probes;

measuring impedance of the differential mode signal probes; and

identifying which of an asymmetric fault condition or a symmetric fault condition is present on the line based on both: (a) the measured CMRR of the differential mode signal probes and (b) the measured impedance of the differential mode signal probes.

2. The method of claim 1 , wherein injecting the differential mode signal probes onto the two conductors of the DSL line comprises injecting inversed differential mode signal probes onto the two conductors of the DSL line.

3. The method of claim 1 , wherein measuring the impedance of the differential mode signal probes comprises measuring a reflectometry waveform.

4. The method of claim 1 , wherein measuring CMRR of the differential mode signal probe comprises converting the measured CMRR to detect the reflectometry waveform.

5. The method of claim 1 , wherein measuring the impedance of the differential mode signal probes comprises measuring a reflection coefficient of the differential mode signal probes and converting the measured reflection coefficient to a reflectometry waveform.

6. The method of claim 1 , further comprising:

correlating the measured common-mode rejection ratio of the differential mode signal probes and the measured impedance of the differential mode signal probes to an asymmetric fault on the DSL line.

7. The method of claim 6 , wherein correlating the measured common-mode rejection ratio of the differential mode signal probes and the measured impedance of the differential mode signal probes to an asymmetric fault on the DSL line comprises:

detecting a first fault the measured common-mode rejection ratio;

detecting a second fault in the measured impedance of the differential mode signal probes;

comparing the first fault detected with the second fault detected; and

determining the first fault and the second fault are due to an asymmetric fault of on the DSL line.

8. The method of claim 7 , wherein the asymmetric fault on the DSL line corresponds to a bad splice fault condition;

wherein the asymmetric fault on the DSL line corresponds to a bad splice fault condition.

9. The method of claim 1 , further comprising:

correlating the measured common-mode rejection ratio of the differential mode signal probes below a minimum threshold indicating no anomaly and the measured impedance of the differential mode signal probes to a symmetric fault on the DSL line.

10. The method of claim 9 , wherein the symmetric fault on the DSL line corresponds to a bridged tap fault condition on the DSL line.

11. The method of claim 1 , wherein injecting the differential mode signal probes onto the DSL line comprises one of:

generating the probes via a differential transmitter embodied within a chipset of a Customer Premises Equipment (CPE) modem communicably interfaced with the first end of the DSL line and injecting the generated probes onto the DSL line;

generating the probes via a differential transmitter embodied within a chipset of a signal conditioning device physically separate and distinct from a Customer Premises Equipment (CPE) modem, wherein the signal conditioning device is communicably interfaced with the first end of the DSL line, wherein the CPE modem is communicatively interfaced to the signal conditioning device, and further wherein the differential transmitter of the signal conditioning device injects the generated probes onto the DSL line;

generating the probes via a differential transmitter embodied within a controller card configured within a Customer Premises Equipment (CPE) modem communicably interfaced with the first end of the DSL line and injecting the generated probes via the differential transmitter of the controller card through the CPE modem;

generating the probes via a differential transmitter embodied within a controller card configured within a signal conditioning device physically separate and distinct from a Customer Premises Equipment (CPE) modem, wherein the signal conditioning device is communicably interfaced with the first end of the DSL line, wherein the CPE modem is communicatively interfaced to the signal conditioning device, and further wherein the differential transmitter of the controller card within the signal conditioning device injects the generated probes onto the DSL line; and

generating the probes via a differential transmitter embodied within a hand-held diagnostics apparatus temporarily connected with the first end of the DSL line and injecting the generated probes via the hand-held diagnostics apparatus.

12. The method of claim 1 , further comprising:

tapping the DSL line with DSL line taps;

wherein injecting the differential mode signal probes comprises transmitting the differential mode signal probes onto the DSL line via the DSL line taps; and

wherein measuring the common-mode rejection ratio (CMRR) and the impedance of the differential mode signal probes comprises receiving via the DSL line taps.

13. The method of claim 12 , wherein a deflector controller controls the transmitting for injecting the differential mode signal probes and wherein the deflector controller further controls the receiving for capturing reflections from the injected differential mode signal probes for analysis.

14. The method of claim 1 , wherein measuring the common-mode rejection ratio of the differential mode signal probes comprises:

receiving a reflection of one of the differential mode signal probes at a common mode receiver; and

deriving the common-mode rejection ratio from the transmitted differential mode signal as received at the common mode receiver.

15. The method of claim 1 , wherein measuring the impedance of the differential mode signal probes comprises identifying a waveform peak and a waveform trough;

wherein the method further comprises:

correlating the waveform trough to a distance from a differential transmitter having generated the differential mode signal probes to a bridged tap on the DSL line; and

correlating the waveform peak to a distance from the differential transmitter having generated the differential mode signal probes to an end-point of the bridged tap, wherein the bridged tap ends at the end-point without termination.

16. The method of claim 1 , wherein measuring the impedance of the differential mode signal probes comprises identifying a waveform shape;

wherein the method further comprises:

deriving a first distance from a differential transmitter having generated the differential mode signal probes to a bridged tap on the DSL line; and

deriving a second distance from the differential transmitter having generated the differential mode signal probes to an end-point of the bridged tap, wherein the bridged tap ends at the end-point without termination.

17. The method of claim 1 , wherein measuring the common-mode rejection ratio of the differential mode signal probes comprises identifying a signal anomaly attributable to a bad splice on the DSL line; and

wherein the method further comprises:

correlating the signal anomaly to a distance from a differential transmitter having generated the differential mode signal probes to the bad splice on the DSL line.

18. An apparatus comprising:

a signal generator to inject differential mode signal probes onto two conductors of a Digital Subscriber Line (DSL line);

a signal detector to measure a common-mode rejection ratio (CMRR) of the differential mode signal probes;

the signal detector to further measure impedance of the differential mode signal probes; and

a signal analyzer to identify which of an asymmetric fault condition or a symmetric fault condition is present on the line based on both: (a) the measured CMRR of the differential mode signal probes and (b) the measured impedance of the differential mode signal probes.

19. The apparatus of claim 18 , wherein the signal detector to measure the impedance of the differential mode signal probes comprises the signal detector to measure a reflection coefficient of the differential mode signal probes and convert the measured reflection coefficient to a reflectometry waveform.

20. The apparatus of claim 18 , wherein the signal analyzer to further correlate the measured common-mode rejection ratio of the differential mode signal probes and the measured impedance of the differential mode signal probes to an asymmetric fault on the DSL line.

21. The apparatus of claim 20 , wherein the asymmetric fault on the DSL line corresponds to a bad splice fault condition.

22. The apparatus of claim 18 , wherein the signal analyzer to further correlate the measured common-mode rejection ratio of the differential mode signal probes below a minimum threshold indicating no anomaly and the measured impedance of the differential mode signal probes to a symmetric fault on the DSL line of a bridged tap fault condition type.

23. The apparatus of claim 18 , wherein the signal generator comprises one of:

a differential transmitter embodied within a chipset of a Customer Premises Equipment (CPE) modem communicably interfaced with the first end of the DSL line to inject the generated probes onto the DSL line;

a differential transmitter embodied within a chipset of a signal conditioning device physically separate and distinct from a Customer Premises Equipment (CPE) modem, wherein the signal conditioning device is communicably interfaced with the first end of the DSL line, wherein the CPE modem is communicatively interfaced to the signal conditioning device, and further wherein the differential transmitter of the signal conditioning device injects the generated probes onto the DSL line;

a differential transmitter embodied within a controller card configured within a Customer Premises Equipment (CPE) modem communicably interfaced with the first end of the DSL line, wherein the differential transmitter of the controller card to inject the generated probes via the CPE modem;

a differential transmitter embodied within a controller card configured within a signal conditioning device physically separate and distinct from a Customer Premises Equipment (CPE) modem, wherein the signal conditioning device is communicably interfaced with the first end of the DSL line, wherein the CPE modem is communicatively interfaced to the signal conditioning device, and further wherein the differential transmitter of the controller card within the signal conditioning device is to inject the generated probes onto the DSL line; and

a differential transmitter embodied within a hand-held diagnostics apparatus temporarily connected with the first end of the DSL line to inject the generated probes via the hand-held diagnostics apparatus.

24. The apparatus of claim 18 , further comprising:

a DSL line tap into each of the two conductors of the DSL line;

wherein the signal generator to generate the differential mode signal probes comprises the signal generator to transmit the differential mode signal probes onto the DSL line via the DSL line taps; and

wherein the signal detector to measure the common-mode rejection ratio (CMRR) and the impedance of the differential mode signal probes comprises the signal detector to receive via the DSL line taps.

25. The apparatus of claim 24 , further comprising:

a deflector controller to control the transmit the differential mode signal probes from the signal generator; and

wherein the deflector controller further to control the receiving via the signal detector for capturing reflections from the injected differential mode signal probes for analysis.

26. The apparatus of claim 18 , further comprising:

a common mode receiver coupled with one of the two conductors of the DSL line;

wherein the signal detector to measure the common-mode rejection ratio of the differential mode signal probes comprises the signal detector to receive a reflection of one of the differential mode signal probes via the common mode receiver; and

wherein the signal analyzer to derive the common-mode rejection ratio from the transmitted differential mode signal as received by the common mode receiver.

27. The apparatus of claim 18 :

wherein the signal generator comprises a differential transmitter to inject the differential mode signal probes; and

wherein the signal analyzer is to further:

a) identify a waveform peak and a waveform trough based on the measured impedance of the differential mode signal probes,

b) correlate the waveform trough to a distance from the differential transmitter having generated the differential mode signal probes to a bridged tap on the DSL line, and

c) correlate the waveform peak to a distance from the differential transmitter having generated the differential mode signal probes to an end-point of the bridged tap, wherein the bridged tap ends at the end-point without termination.

28. The apparatus of claim 18 :

wherein the signal generator comprises a differential transmitter to inject the differential mode signal probes; and

wherein the signal analyzer is to further:

a) identify a signal anomaly attributable to a bad splice on the DSL line, and

b) correlate the signal anomaly to a distance from a differential transmitter having generated the differential mode signal probes to the bad splice on the DSL line.

29. A non-transitory computer readable storage medium having instructions stored thereon that, when executed by a processor of an apparatus, the instructions cause the apparatus to perform operations comprising:

injecting differential mode signal probes onto two conductors of a Digital Subscriber Line (DSL line);

measuring a common-mode rejection ratio (CMRR) of the differential mode signal probes;

measuring impedance of the differential mode signal probes; and

identifying which of an asymmetric fault condition or a symmetric fault condition is present on the line based on both: (a) the measured CMRR of the differential mode signal probes and (b) the measured impedance of the differential mode signal probes.

30. The non-transitory computer readable storage medium of claim 29 , wherein measuring the impedance of the differential mode signal probes comprises measuring a reflectometry waveform.

31. The non-transitory computer readable storage medium of claim 29 , wherein measuring CMRR of the differential mode signal probe comprises converting the measured CMRR to detect the reflectometry waveform.

32. The non-transitory computer readable storage medium of claim 29 :

wherein measuring the impedance of the differential mode signal probes comprises measuring a reflection coefficient of the differential mode signal probes and converting the measured reflection coefficient to a reflectometry waveform; and

wherein the instructions cause the apparatus to perform operations further comprising correlating the measured common-mode rejection ratio of the differential mode signal probes and the measured impedance of the differential mode signal probes to an asymmetric fault on the DSL line of a bad splice fault condition type.

33. The non-transitory computer readable storage medium of claim 29 , wherein the instructions cause the apparatus to perform operations further comprising correlating the measured common-mode rejection ratio of the differential mode signal probes below a minimum threshold indicating no anomaly and the measured impedance of the differential mode signal probes to a symmetric fault on the DSL line of a bridged tap fault condition type.

34. The non-transitory computer readable storage medium of claim 29 , wherein injecting the differential mode signal probes onto the DSL line comprises one of:

generating the probes via a differential transmitter embodied within a chipset of a Customer Premises Equipment (CPE) modem communicably interfaced with the first end of the DSL line and injecting the generated probes onto the DSL line;

generating the probes via a differential transmitter embodied within a chipset of a signal conditioning device physically separate and distinct from a Customer Premises Equipment (CPE) modem, wherein the signal conditioning device is communicably interfaced with the first end of the DSL line, wherein the CPE modem is communicatively interfaced to the signal conditioning device, and further wherein the differential transmitter of the signal conditioning device injects the generated probes onto the DSL line;

generating the probes via a differential transmitter embodied within a controller card configured within a Customer Premises Equipment (CPE) modem communicably interfaced with the first end of the DSL line and injecting the generated probes via the differential transmitter of the controller card through the CPE modem;

generating the probes via a differential transmitter embodied within a controller card configured within a signal conditioning device physically separate and distinct from a Customer Premises Equipment (CPE) modem, wherein the signal conditioning device is communicably interfaced with the first end of the DSL line, wherein the CPE modem is communicatively interfaced to the signal conditioning device, and further wherein the differential transmitter of the controller card within the signal conditioning device injects the generated probes onto the DSL line; and

generating the probes via a differential transmitter embodied within a hand-held diagnostics apparatus temporarily connected with the first end of the DSL line and injecting the generated probes via the hand-held diagnostics apparatus.

35. The non-transitory computer readable storage medium of claim 29 , wherein measuring the impedance of the differential mode signal probes comprises identifying a waveform shape; and

wherein the instructions cause the apparatus to perform operations further comprising:

deriving a first distance from a differential transmitter having generated the differential mode signal probes to a bridged tap on the DSL line, and

deriving a second distance from the differential transmitter having generated the differential mode signal probes to an end-point of the bridged tap, wherein the bridged tap ends at the end-point without termination.

36. The non-transitory computer readable storage medium of claim 29 :

wherein measuring the common-mode rejection ratio of the differential mode signal probes comprises identifying a signal anomaly attributable to a bad splice on the DSL line; and

wherein the instructions cause the apparatus to perform operations further comprising correlating the signal anomaly to a distance from a differential transmitter having generated the differential mode signal probes to the bad splice on the DSL line.

37. The non-transitory computer readable storage medium of claim 29 , wherein identifying which of an asymmetric fault condition or a symmetric fault condition is present on the line based on both: (a) the measured CMRR of the differential mode signal probes and (b) the measured impedance of the differential mode signal probes comprises:

sending the common-mode rejection ratio (CMRR) of the differential mode signal probes as measured and the impedance of the differential mode signal probes as measured to a remote entity for signal analysis.

Assignments (11)