Full duplex voice path capture buffer with time stamp

• US 20030174694A1
• Filed: 01/06/2003
• Published: 09/18/2003
• Est. Priority Date: 03/12/2002
• Status: Active Grant

• Current Assignee: ADTRAN Incorporated (ADTRAN Holdings, Inc.)
• Original Assignee: ADTRAN Incorporated (ADTRAN Holdings, Inc.)
• Inventors: Otto, Christopher A., Mitchell, Bruce E.
• Granted Patent: US 7,366,161 B2
• Time in Patent Office: Days
• US Class Current: 370/352
• CPC Class Codes: H04L 12/5601 Transfer mode dependent, e.g. ATM
• CPC Class Codes: H04L 2012/5656 using the AAL2
• CPC Class Codes: H04L 2012/5671 Support of voice
• CPC Class Codes: H04Q 11/04 for time-division multiplexing H04Q11/0001 takes precedence
• CPC Class Codes: H04Q 2213/13034 A/D conversion, code compression/expansion
• CPC Class Codes: H04Q 2213/1319 Amplifier, attenuation circuit, echo suppressor
• CPC Class Codes: H04Q 2213/1329 Asynchronous transfer mode, ATM
• CPC Class Codes: H04Q 2213/13292 Time division multiplexing, TDM

Abstract

For diagnostic and trouble-shooting purposes, an audio/voice signal capture mechanism is adapted to be interfaced with a time division multiplexed (TDM) transport path-cascaded echo canceler and compression arrangement for an integrated access device (IAD). The audio/voice signal capture mechanism captures a ‘snapshot’ of the audio/voice signals by storing a prescribed number of seconds of audio/voice path signals transmitted in both directions through the IAD, and time stamping the captured audio/voice signals and associated signaling events of interest. In this way, the invention operates as a ‘virtual’ oscilloscope, as it is able to capture pertinent data for any voice call problem along with an associated time stamp event log.

Claims

1. For use with a processor-controlled digital communication device adapted to process digitally encoded audio signals transported over a time division multiplex (TDM) communication path for assembly in accordance with a communication protocol, so that said audio signals may be transmitted over a digital communication link to a destination device, a method comprising the steps of:

(a) storing a prescribed quantity of said digitally encoded audio signals; and

(b) coupling said prescribed quantity of digitally encoded audio signals to a signal waveform analysis operator.

2. The method according to claim 1, wherein step (a) further includes storing time stamp information representative of the time of occurrence of said prescribed quantity of digitally encoded audio signals relative to a prescribed time base, and step (b) further includes coupling said time stamp information to signal waveform analysis operator, so that said prescribed quantity of digitally encoded audio signals may be associated said time stamp information therefor by said signal waveform analysis operator.

3. The method according to claim 2, wherein said step (b) includes providing an output representation of said prescribed quantity of audio signals relative to timing information of said prescribed time base.

4. The method according to claim 1, wherein said processor-controlled digital communication device is operative to perform echo cancellation and compression of said digitally encoded audio signals as received from said TDM communication path, and to couple compressed, echo cancellation-processed audio signals over said TDM communication path to a host processor of said processor-controlled digital communication device, said host processor storing said prescribed quantity of digitally encoded audio signals in accordance with step (a), and coupling said prescribed quantity of digitally encoded audio signals to said signal waveform analysis operator in accordance with step (b).

5. The method according to claim 1, wherein said processor-controlled digital communication device comprises an integrated access device.

6. The method according to claim 1, wherein said echo cancellation comprises ITU G.168 echo cancellation and said compression comprises ITU G.726 adaptive differential pulse code modulation (ADPCM) compression.

7. The method according to claim 1, wherein said signal waveform analysis operator is operative to perform one of time and frequency domain analysis.

8. The method according to claim 1, wherein step (a) further includes storing a predetermined quantity of signaling events as supplied to said processor-controlled digital communication device by way of said digital communication link from said destination device, and step (b) comprises coupling said predetermined quantity of signaling events to said signal waveform analysis operator.

9. The method according to claim 8, wherein step (a) further includes storing time stamp information representative of the time of occurrence of said predetermined quantity of signaling events relative to said prescribed time base, and step (b) further includes coupling said time stamp information to signal waveform analysis operator, so that said predetermined quantity of signaling events may be associated said time stamp information therefor by said signal waveform analysis operator.

10. The method according to claim 9, wherein said step (b) includes providing an output representation of said predetermined quantity of signaling events relative to timing information of said prescribed time base.

11. A signal processing mechanism adapted for use with a processor-controlled digital communication device adapted to process digitally encoded audio signals transported over a time division multiplex (TDM) communication path for assembly in accordance with a communication protocol, so that said audio signals may be transmitted over a digital communication link to a destination device, said signal processing arrangement comprising:

a memory which is operative to store a prescribed quantity of said digitally encoded audio signals; and

a stored signal transport path which is operative to couple said prescribed quantity of digitally encoded audio signals to a signal waveform analysis operator.

12. The signal processing mechanism according to claim 11, wherein said memory is operative to store time stamp information representative of the time of occurrence of said prescribed quantity of digitally encoded audio signals relative to a prescribed time base, and said signal transport path is operative to couple said time stamp information to signal waveform analysis operator, so that said prescribed quantity of digitally encoded audio signals may be associated said time stamp information therefor by said signal waveform analysis operator.

13. The signal processing mechanism according to claim 12, wherein said signal waveform analysis operator is operative to provide an output representation of said prescribed quantity of audio signals relative to timing information of said prescribed time base.

14. The signal processing mechanism according to claim 11, wherein said processor-controlled digital communication device is operative to perform echo cancellation and compression of said digitally encoded audio signals as received from said TDM communication path, and to couple compressed, echo cancellation-processed audio signals over said TDM communication path to a host processor of said processor-controlled digital communication device, said host processor being coupled with said memory storing said prescribed quantity of digitally encoded audio signals, and coupling said prescribed quantity of digitally encoded audio signals to said signal transport path for delivery to said signal waveform analysis operator.

15. The signal processing mechanism according to claim 11, wherein said signal waveform analysis operator is operative to perform one of time and frequency domain analysis.

16. The signal processing mechanism according to claim 11, wherein said memory is operative to store a predetermined quantity of signaling events as supplied to said processor-controlled digital communication device by way of said digital communication link from said destination device, and said signal transport path is operative to couple said predetermined quantity of signaling events to said signal waveform analysis operator.

17. The signal processing mechanism according to claim 16, wherein said memory is operative to store time stamp information representative of the time of occurrence of said predetermined quantity of signaling events relative to said prescribed time base, and said signal transport path is operative to couple said time stamp information to signal waveform analysis operator, so that said predetermined quantity of signaling events may be associated said time stamp information therefor by said signal waveform analysis operator.

18. The signal processing operator according to claim 17, wherein said signal waveform analysis operator is operative to provide an output representation of said predetermined quantity of signaling events relative to timing information of said prescribed time base.