Microphone apparatus and method for removing unwanted sounds

Patent metadata

Field	Value
Publication number	US-9549252-B2
Application number	US-201013819115-A
Country	US
Kind code	B2
Filing date	Aug 27, 2010
Priority date	Aug 27, 2010
Publication date	Jan 17, 2017
Grant date	Jan 17, 2017

Abstract

An apparatus comprises a first transducer configured to detect sound and generate a first signal based on the detected sound. The apparatus also comprises a second transducer configured to detect vibration and/or sound and generate a second signal based on the detected vibrations and/or sound. The second transducer is less acoustically responsive than the first transducer. The apparatus comprises an interface configured to send the first and second signals to a processor configured to modify the first signal on the basis of the second signal.

First claim

The invention claimed is:

1. An apparatus comprising an audio module configured to capture sound,
the audio module comprising:
a first membrane configured to detect sound and generate a first signal based on the detected sound; and
a second membrane configured to detect vibration and/or sound and generate a second signal based on the detected vibration and/or sound, the second membrane being less acoustically responsive than the first membrane; and
an interface configured to send the first and second signals to a processor configured to modify the first signal on the basis of the second signal so as to remove unwanted vibrations and/or sounds from the first signal;
wherein the first membrane and the second membrane are disposed adjacent to each other on a same substrate.

2. The apparatus according claim 1 , wherein the processor is configured to modify the first signal on the basis of the second signal by subtracting the second signal from the first signal.

3. The apparatus according to claim 1 wherein the unwanted vibration and/or sound that the second membrane is configured to detect comprises one or more of the following: vibrations of the apparatus, wind noise, handling of the apparatus and unwanted sound.

4. The apparatus according to claim 1 wherein the second membrane is less acoustically responsive than the first membrane due to the second membrane being at least one of:
responsive to one or more different frequency ranges relative to the first membrane, and
tuned to one or more frequency ranges of unwanted vibrations.

5. The apparatus according to claim 1 wherein the interface comprises a first interface for sending the first signal on a first channel to the processor and a second interface for sending the second signal on a second channel to the processor.

6. The apparatus according to claim 1 wherein the processor is further configured to align the phases of the first signal and the second signal.

7. The apparatus according to claim 1 wherein the processor is further configured to align amplitudes of the first signal and the second signal.

8. The apparatus according to claim 1 wherein the second membrane is less acoustically responsive than the first membrane due to a higher stiffness of the second membrane relative to the first membrane.

9. The apparatus according to claim 1 wherein the first signal is from at least one audio source and the second signal is from at least one other source other than the audio source.

10. The apparatus according to claim 1 , wherein the processor is disposed on the same substrate as the first membrane and the second membrane.

11. The apparatus according to claim 1 , wherein the audio module further comprises an amplifier disposed on the same substrate as the first membrane and the second membrane, and the processor is not disposed on the same substrate.

12. The apparatus according to claim 1 , wherein the second membrane is less acoustically responsive than the first membrane due to a physical cover over the second membrane that acoustically isolates the second membrane from an environment of the first membrane.

13. The apparatus according to claim 12 , wherein the physical cover seals the second membrane from the first membrane.

14. The apparatus according to claim 13 . wherein there is at least a partial vacuum between the physical cover and the second membrane.

15. The apparatus according to claim 14 , wherein the first membrane and the second membrane have substantially identical audio sensitivities, and the at least partial vacuum substantially equalizes audio sensitivity of the second membrane with audio sensitivity of the first membrane.

16. The apparatus according to claim 1 , wherein the interface comprises a single data line comprising two channels for the respective first signal and second signal.

17. The apparatus according to claim 1 , further comprising a switch configured to selectively block the second signal:
in response to a manual user input, and/or
automatically when a level of the second signal is less than a prescribed threshold.

18. A method comprising:
detecting sound with a first membrane in an audio module;
generating a first signal based on the detected sound;
detecting vibration and/or sound with a second membrane in the audio module, the second membrane being less acoustically responsive than the first membrane and wherein the first membrane and the second membrane are disposed adjacent to each other on a same substrate;
generating a second signal based on the detected vibration and/or sound; and
sending the first and second signals to a processor configured to modify the first signal on the basis of the second signal so as to remove unwanted vibrations and/or sounds from the first signal.

19. The method according to claim 18 wherein the method comprises modifying the first signal on the basis of the second signal.

20. The method according to claim 19 wherein the modifying comprises subtracting the second signal from the first signal.

21. The method according to claim 19 wherein the modifying comprises aligning at least one of:
phases of the first signal and the second signal; and
amplitudes of the first signal and the second signal.

Assignees

• Suvanto Mikko Veli Aimo
• Nokia Technologies Oy

Inventors

• Suvanto Mikko Veli Aimo

Classifications

• G10L21/0216

  characterised by the method used for estimating noise · CPC title

• H04R2201/003

  Mems transducers or their use · CPC title

• H04R2410/05

  Noise reduction with a separate noise microphone · CPC title

• H04R3/005 Primary

  for combining the signals of two or more microphones (specially adapted for hearing aids H04R25/407) · CPC title

• G10K2210/129

  Vibration, e.g. instead of, or in addition to, acoustic noise · CPC title