Method and system for a subband acoustic echo canceller with integrated voice activity detection

• US 8,982,744 B2
• Filed: 06/06/2007
• Issued: 03/17/2015
• Est. Priority Date: 06/06/2007
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Sanyal, Sumit, LeBlanc, Wilfrid
• Primary Examiner(s): Phillips, Hassan
• Assistant Examiner(s): JONES, PRENELL P
• Application Number:
  US11/758,928
• Publication Number:
  US 20080306736A1
• Time in Patent Office: 2,841 Days
• Field of Search: 370/286, 370/320, 370/289, 370/208, 370/335, 370/342, 370/441, 370/311, 370/337, 370/310, 370/338, 370/344, 370/401, 370/328, 379/406, 379/388, 379/56, 379/217, 379/341, 379/238, 379/417, 375/260, 375/241, 375/346, 375/141, 704/200, 704/233, 704/215, 704/231, 704/224, 705/38, 705/37, 705/35, 705/1, 705/80, 455/450, 455/522, 455/41, 455/570, 455/79, 455/226, 455/69, 455/557, 455/343, 345/156, 340/815, 725/131, 241/36
• US Class Current: 370/286
• CPC Class Codes: G10L 19/00 Speech or audio signals analysis-synthesis techniques for redundancy reduction, e.g. in vocoders; Coding or decoding of speech or audio signals, using source filter models or psychoacoustic analysis in musical instruments G10H
• CPC Class Codes: G10L 25/78 Detection of presence or absence of voice signals switching of direction of transmission by voice frequency in two-way loud-speaking telephone systems H04M9/10
• CPC Class Codes: H04M 9/085 using digital techniques H04M9/082 takes precedence
• CPC Class Codes: H04W 52/287 when the channel is in stand-by

Abstract

Methods and systems for a subband acoustic echo canceller with integrated voice activity detection are disclosed and may include adjusting transmit and/or receive powers of wirelessly communicated audio signals based on voice activity detection via subband analysis of the wirelessly communicated audio signals. The receive power may be adjusted by utilizing a reduced duty cycle, or by conveying voice activity detection information via an asynchronous control channel in a Bluetooth application. A plurality of subbands may be generated utilizing a fast Fourier transform, and a first subset of the subbands corresponding to voice activity may be selected and a second subset of the subbands may be selected that corresponds to background noise. The processing of the subsets may be dynamically adjusted due to variations in the voice activity or background noise. Comfort noise may be generated and transmitted at a reduced bandwidth utilizing the second subset of the subbands.

Claims

1. A method for a wireless system control, the method comprising:

in a receiver;

while receiving wirelessly communicated audio signals, determining a voice activity based on a subband analysis of said wirelessly communicated audio signals;

adjusting an amount of power used for a wireless reception in said receiver based on said voice activity;

generating a plurality of subbands for said subband analysis;

processing a second subset of said plurality of subbands; and

generating a comfort noise based on said processed second subset of said plurality of subbands.

2. The method according to claim 1, wherein said adjusting comprises reducing a duty cycle for receiving said wirelessly communicated audio signals.

3. The method according to claim 1, wherein said adjusting comprises:

conveying voice activity detection information via an asynchronous control channel for wireless communications; and

selectively disabling a wireless data packet reception of said wirelessly communicated audio signals based on said voice activity detection information.

4. The method according to claim 1, wherein said adjusting comprises adjusting an amount of power used for a wireless transmission in said receiver based on said voice activity.

5. The method according to claim 4, comprising performing said subband analysis based on egress and ingress echo cancellation subband analysis information within a subband acoustic echo canceller.

6. The method according to claim 1, comprising generating the plurality of subbands for said subband analysis utilizing a fast Fourier transform.

7. The method according to claim 6, comprising processing a first subset of said plurality of subbands, said first subset of said plurality of subbands corresponding to the voice activity in said wirelessly communicated audio signals.

8. The method according to claim 7, comprising dynamically adjusting said processing to correspond to variations in said voice activity in said wirelessly communicated audio signals.

9. The method according to claim 7, comprising determining the voice activity in said wirelessly communicated audio signals based on said first subset of said plurality of subbands.

10. The method according to claim 6, wherein said second subset of said plurality of subbands corresponds to a background noise in said wirelessly communicated audio signals.

11. The method according to claim 10, comprising dynamically adjusting said processing to correspond to variations in said background noise in said wirelessly communicated audio signals.

12. The method according to claim 1, transmitting said comfort noise utilizing a reduced bandwidth.

13. A system for a wireless system control, the system comprising:

a receiver that handles processing of wirelessly communicated audio signals, said receiver comprising;

acoustic echo canceller circuitry operable to,

while receiving wirelessly communicated audio signals, determining a voice activity based on a subband analysis of wirelessly communicated audio signals;

generating a plurality of subbands for said subband analysis;

processing a second subset of said plurality of subbands; and

generating a comfort noise based on said second subset of said plurality of subbands; and

communications circuitry operable to adjust an amount of power used for a wireless reception in said receiver based on said voice activity.

14. The system according to claim 13, wherein said communications circuitry is further operable to reduce a duty cycle for receiving said wirelessly communicated audio signals.

15. The system according to claim 13, wherein said communications circuitry is further operable to:

convey voice activity detection information via an asynchronous control channel for wireless communications; and

selectively disable a wireless data packet reception of said wirelessly communicated audio signals based on said voice activity detection information.

16. The system according to claim 13, wherein said communications circuitry is further operable to adjust an amount of power used for a wireless transmission in said receiver based on said voice activity.

17. The system according to claim 13, wherein said acoustic echo canceller circuitry is further operable to generate the plurality of subbands for said subband analysis utilizing a fast Fourier transform.

18. The system according to claim 17, wherein said acoustic echo canceller circuitry is further operable to process a first subset of said plurality of subbands, said first subset of said plurality of subbands corresponding to the voice activity in said wirelessly communicated audio signals.

19. The system according to claim 18, wherein said acoustic echo canceller circuitry is further operable to dynamically adjust said processing to correspond to variations in said voice activity in said wirelessly communicated audio signals.

20. The system according to claim 18, wherein said acoustic echo canceller circuitry is further operable to determine the voice activity in said wirelessly communicated audio signals based on said first subset of said plurality of subbands.

21. The system according to claim 17, wherein said second subset of said plurality of subbands corresponds to background noise in said wirelessly communicated audio signals.

22. The system according to claim 21, wherein said acoustic echo canceller circuitry is further operable to dynamically adjust said processing to correspond to variations in said background noise in said wirelessly communicated audio signals.

23. The system according to claim 13, wherein said acoustic echo canceller circuitry is further operable to transmit said comfort noise utilizing a reduced bandwidth.

24. A non-transitory computer readable storage having stored thereon, a computer program having at least one code section, the at least one code section being executable by a machine for causing the machine to perform a method for a wireless system control, comprising:

in a receiver;

while receiving wirelessly communicated audio signals, determining a voice activity based on a subband analysis of received wirelessly communicated audio signals;

adjusting an amount of power used for a wireless reception in said receiver based on said voice activity;

generating a plurality of subbands for said subband analysis;

processing a second subset of said plurality of subbands; and

generating a comfort noise based on said processed second subset of said plurality of subbands.

25. The non-transitory computer readable storage according to claim 24, wherein said adjusting comprises reducing a duty cycle for receiving said wirelessly communicated audio signals.

26. The non-transitory computer readable storage according to claim 24, wherein said adjusting comprises:

conveying voice activity detection information via an asynchronous control channel for wireless communications; and

selectively disabling a wireless data packet reception of said wirelessly communicated audio signals based on said voice activity detection information.

27. The non-transitory computer readable storage according to claim 24, wherein said adjusting comprises adjusting an amount of power used for a wireless transmission in said receiver based on said voice activity.

28. The non-transitory computer readable storage according to claim 27, the method comprising performing said subband analysis based on egress and ingress echo cancellation subband analysis information within a subband acoustic echo canceller.

29. The non-transitory computer readable storage according to claim 24, the method comprising generating the plurality of subbands for said subband analysis utilizing a fast Fourier transform.

30. The non-transitory computer readable storage according to claim 29, the method comprising processing a first subset of said plurality of subbands, said first subset of said plurality of subbands corresponding to the voice activity in said wirelessly communicated audio signals.

31. The non-transitory computer readable storage according to claim 30, the method comprising dynamically adjusting said processing to correspond to variations in said voice activity in said wirelessly communicated audio signals.

32. The non-transitory computer readable storage according to claim 30, the method comprising determining the voice activity in said wirelessly communicated audio signals based on said first subset of said plurality of subbands.

33. The non-transitory computer readable storage according to claim 29, wherein said second subset of said plurality of subbands corresponds to background noise in said wirelessly communicated audio signals.

34. The non-transitory computer readable storage according to claim 33, the method comprising dynamically adjusting said processing to correspond to variations in said background noise in said wirelessly communicated audio signals.

35. The non-transitory computer readable storage according to claim 24, the method comprising transmitting said comfort noise utilizing a reduced bandwidth.