Voice Activity Detection With Capacitive Touch Sense

• US 20090252351A1
• Filed: 04/02/2008
• Published: 10/08/2009
• Est. Priority Date: 04/02/2008
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Plantronics, Inc.
• Inventors: Rosener, Douglas K.
• Granted Patent: US 9,094,764 B2
• Time in Patent Office: Days
• US Class Current: 381/151
• CPC Class Codes: H04R 19/00 Electrostatic transducers
• CPC Class Codes: H04R 2460/13 Hearing devices using bone conduction transducers

Abstract

A voice activity detection apparatus having a capacitive sensor and a voice activity detector sensor. The voice activity detector sensor detects vibration of human tissue associated with user speech. Utilization of the voice activity detector sensor output is tied to the output of the capacitive sensor, where the capacitive sensor detects whether it is in contact with user skin.

Claims

1. A voice activity detection apparatus comprising:

a capacitive sensor providing a capacitive sensor output signal, wherein the capacitive sensor detects whether the capacitive sensor is in contact with a user skin;

a voice activity detector sensor providing a voice activity detector sensor output signal, wherein the voice activity detector sensor detects vibration of human tissue associated with user speech; and

a processor which receives the capacitive sensor output signal and the voice activity detector sensor output signal, wherein the voice activity detector sensor output signal is processed to determine a voice activity status only if the capacitive sensor output signal indicates that the capacitive sensor is in contact with the user skin.

2. The voice activity detection apparatus of claim 1, wherein the voice activity detector sensor comprises a tissue vibration detector.

3. The voice activity detection apparatus of claim 1, wherein the voice activity detector sensor comprises one selected from the following group:

a bone conduction microphone, an accelerometer, a tissue conduction microphone, and a capacitance sensor.

4. The voice activity detection apparatus of claim 1, further comprising an acoustic microphone providing an acoustic microphone output signal, wherein the acoustic microphone detects acoustic air waves associated with user speech, and wherein the acoustic microphone output signal is processed to determine a voice activity status.

5. The voice activity detection apparatus of claim 4, wherein the acoustic microphone output signal is processed to determine a voice activity status only if the capacitive sensor output signal indicates that the capacitive sensor is not in contact with the user skin.

6. The voice activity detection apparatus of claim 1, further comprising a housing having an exterior surface on which the capacitive sensor and the voice activity detector sensor are disposed adjacent to each other.

7. A voice activity detection apparatus comprising:

a first capacitive sensor providing a first capacitive sensor output signal, wherein the first capacitive sensor detects whether the first capacitive sensor is in contact with a user skin;

a second capacitive sensor providing a second capacitive sensor output signal, wherein the second capacitive sensor detects whether the second capacitive sensor is in contact with a user skin;

a voice activity detector sensor providing a voice activity detector sensor output signal, wherein the voice activity detector sensor detects vibration of human tissue associated with user speech;

a processor which receives the first capacitive sensor output signal, the second capacitive sensor output signal and the voice activity detector sensor output signal, wherein the voice activity detector sensor output signal is processed to determine a voice activity status only if both the first capacitive sensor output signal indicates that the first capacitive sensor is in contact with the user skin and the second capacitive sensor output signal indicates that the second capacitive sensor is in contact with the user skin.

8. The voice activity detection apparatus of claim 7, wherein the voice activity detector sensor comprises a tissue vibration detector.

9. The voice activity detection apparatus of claim 7, wherein the voice activity detector sensor comprises one selected from the following group:

a bone conduction microphone, an accelerometer, a tissue conduction microphone, and a capacitance sensor.

10. The voice activity detection apparatus of claim 7, further comprising a housing having an exterior surface on which the first capacitive sensor, the second capacitive sensor, and the voice activity detector sensor are disposed, wherein the first capacitive sensor and the second capacitive sensor are disposed on opposite sides of the voice activity detector sensor.

11. The voice activity detection apparatus of claim 10, wherein the first capacitive sensor and the second capacitive sensor are adjacent to the voice activity detector sensor.

12. The voice activity detection apparatus of claim 7, further comprising:

a housing having an exterior surface on which the first capacitive sensor, the second capacitive sensor, and the voice activity detector sensor are disposed;

a receiver for outputting an audio signal, wherein the first capacitive sensor is located in close proximity to the receiver and the second capacitive sensor is located in close proximity to the voice activity detector sensor.

13. The voice activity detection apparatus of claim 7, further comprising:

a third capacitive sensor providing a third capacitive sensor output signal that is output to the processor, wherein the third capacitive sensor detects whether the third capacitive sensor is in contact with a user skin.

14. The voice activity detection apparatus of claim 13, further comprising a housing having an exterior surface on which the first capacitive sensor, the second capacitive sensor, the third capacitive sensor, and the voice activity detector sensor are disposed, wherein the first capacitive sensor, second capacitive sensor, and third capacitive sensor are disposed in a circular pattern around the voice activity detector sensor.

15. A voice activity detection method comprising:

providing a capacitive sensor and a voice activity detector sensor;

outputting a capacitive sensor output signal indicating whether the capacitive sensor is in contact with a user skin;

outputting a voice activity detector sensor output signal;

processing the voice activity detector sensor output signal to determine a voice activity status only if the capacitive sensor output signal indicates that the capacitive sensor is in contact with the user skin.

16. The voice activity detection method of claim 15, further comprising:

providing an acoustic microphone outputting an acoustic microphone output signal; and

processing the acoustic microphone output signal to determine a voice activity status if the capacitive sensor output signal indicates no contact with the user skin.

17. The voice activity detection method of claim 15, further comprising:

providing an acoustic microphone which outputs an acoustic microphone output signal; and

processing the acoustic microphone output signal in conjunction with the voice activity status to reduce noise in the acoustic microphone output signal.

18. The voice activity detection method of claim 15, wherein the voice activity detector sensor comprises a tissue vibration detector.

19. The voice activity detection method of claim 15, wherein the voice activity detector sensor comprises one selected from the following group:

a bone conduction microphone, an accelerometer, a tissue conduction microphone, and a capacitance sensor.

20. A voice activity detection method comprising:

providing a first capacitive sensor, second capacitive sensor, and a voice activity detector sensor;

outputting a first capacitive sensor output signal indicating whether the first capacitive sensor is in contact with a user skin;

outputting a second capacitive sensor output signal indicating whether the second capacitive sensor is in contact with the user skin;

outputting a voice activity detector sensor output signal; and

processing the voice activity detector sensor output signal to determine a voice activity status only if both the first capacitive sensor and the second capacitive sensor are in contact with the user skin.

21. The voice activity detection method of claim 20, further comprising:

providing an acoustic microphone outputting an acoustic microphone output signal; and

processing the acoustic microphone output signal to determine a voice activity status if both or either of the first capacitive sensor output signal and second capacitive sensor output signal indicate no contact with the user skin.

22. The voice activity detection method of claim 20, wherein the voice activity detector sensor comprises a tissue vibration detector.

23. The voice activity detection method of claim 20, wherein the voice activity detector sensor comprises one selected from the following group:

a bone conduction microphone, an accelerometer, a tissue conduction microphone, and a capacitance sensor.

24. A voice activity detection apparatus comprising:

a skin contact sensing means for determining contact with a user skin;

a tissue vibration sensing means for detecting vibration of human tissue associated with user speech; and

a processing means for processing an output of the tissue vibration sensing means to determine a voice activity status only if the skin contact sensing means is in contact with the user skin.

25. The voice activity detection apparatus of claim 24, further comprising a housing means for disposing the skin contact sensing means on and the tissue vibration sensing means on, wherein the tissue vibration sensing means is disposed adjacent the skin contact sensing means.