APPARATUS INCLUDING MICROPHONE ARRANGEMENTS

• US 20100195838A1
• Filed: 02/03/2009
• Published: 08/05/2010
• Est. Priority Date: 02/03/2009
• Status: Active Grant

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Corporation
• Inventors: Bright, Andrew P.
• Granted Patent: US 8,548,176 B2
• Time in Patent Office: Days
• US Class Current: 381/57
• CPC Class Codes: H04M 1/0264 for a camera module assembly
• CPC Class Codes: H04M 1/03 Constructional features of telephone transmitters or receivers, e.g. telephone hand-sets
• CPC Class Codes: H04M 2250/12 including a sensor for measuring a physical value, e.g. temperature or motion telephones including GPS signal receivers H04M2250/10
• CPC Class Codes: H04R 1/1083 Reduction of ambient noise active noise reduction per se G10K11/175; protective devices for the ear, e.g. providing acoustic protection A61F11/06
• CPC Class Codes: H04R 1/406 microphones
• CPC Class Codes: H04R 2410/01 Noise reduction using microphones having different directional characteristics
• CPC Class Codes: H04R 2430/21 Direction finding using differential microphone array [DMA]
• CPC Class Codes: H04R 3/002 Damping circuit arrangements for transducers, e.g. motional feedback circuits
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407

Abstract

An apparatus includes first and second microphone arrangements, arranged to output first and second signals respectively and is operable in a first mode and a second mode. In the first mode, an output signal is generated based on the second signal and a third signal, where the second signal and, optionally, the first signal, can be used to compensate for ambient noise, for example, for noise cancellation when a telephone call is relayed through a speaker. In the second mode, an output signal is generated based on the first and second signals. In this manner, the combination of the first and second microphone arrangements provides a directional sensitivity that can pick up sound from a remote source, for example, in an audio or video recording session. The apparatus may include a sensor to allow automatic switching between one or more of modes, directional sensitivity patterns and types of recording session.

Claims

1. An apparatus including:

first and second microphone arrangements, arranged to output first and second signals respectively;

an audio output;

a controller arranged to generate an output signal;

wherein the apparatus is operable in a first mode and a second mode; and

the controller is arranged to;

generate the output signal based on the second signal and a third signal, where the second signal is used to compensate for ambient noise in the environment of the apparatus, and forward the output signal to the audio output when the apparatus is operated in the first mode; and

generate an output signal based on the first and second signals when the apparatus is operated in the second mode.

2. An apparatus according to claim 1, wherein the controller is configured to use an adaptive filter to generate an anti-noise signal based on the second signal and to tune the adaptive filter according to the first signal when the apparatus is operated in the first mode.

3. An apparatus according to claim 1, configured to provide a direction-dependent sensitivity pattern when using the first and second microphones when the apparatus is operated in the second mode.

4. An apparatus according to claim 1, wherein said direction-dependent sensitivity pattern is a first order gradient pattern.

5. An apparatus according to claim 4, wherein said first order gradient pattern is a cardioid or super-cardioid.

6. An apparatus according to claim 1, comprising:

a camera unit; and

a memory;

wherein;

the controller is operable to store the output signal and video data generated by the camera unit in the memory.

7. An apparatus according to claim 6, wherein the first and second microphones are arranged parallel to an axis of the video camera.

8. An apparatus according to claim 6, comprising a sensor, wherein:

the controller is arranged to determine, based on an output of the sensor, whether to generate video data from the camera unit for storage in the memory.

9. An apparatus according to claim 1, comprising a sensor, wherein:

the controller is arranged to determine, based on an output of the sensor, whether the apparatus is to process the first and second signals or to operate in a third mode in which signals from a third microphone arrangement are processed.

10. An apparatus according to claim 9, wherein the first and second microphone arrangements provides a directional sensitivity pattern when the apparatus is operated in the second mode and the third microphone arrangement provides an omni-directional sensitivity pattern when the apparatus is operated in the third mode.

11. An apparatus according to claim 1, comprising a sensor, wherein:

the controller is arranged to determine, based on an output of the sensor, whether the apparatus is to operate in the first mode or in a third mode that utilises an alternative microphone arrangement.

12. An apparatus according to claim 9, wherein the sensor is a photodetector.

13. An apparatus according to claim 11, wherein the sensor is a photodetector.

14. An apparatus according to claim 1, in the form of a mobile telecommunications device, wherein the third signal is received from a telecommunications network.

15. A method comprising:

operating an apparatus having first and second microphones, arranged to output first and second signals respectively, in first and second operational modes;

when the apparatus is operated in a first mode, generating an output signal based on the second signal and a third signal, where the second signal is used to compensate for ambient noise in the environment of the apparatus, and forwarding the output signal to the audio output; and

when the apparatus is operated in the second mode, generating an output signal based on the first and second signals.

16. A method according to claim 15, wherein:

the generating of the output signal when the apparatus is operated in the first mode includes using an adaptive filter to generate an anti-noise signal based on the second signal;

the method comprising tuning the adaptive filter based on the first signal.

17. A method according to claim 15, comprising:

obtaining a video signal from a camera unit of the apparatus; and

storing the output signal and the video signal in a memory of the apparatus.

18. A method according to claim 15, comprising:

obtaining an output from a sensor; and

determining, based on the sensor output, whether to generate video data from the camera unit for storage in the memory.

19. A method according to claim 15, comprising:

obtaining an output from a sensor; and

determining, based on the sensor output, whether the apparatus is to operate in the second mode or in a third mode wherein, in the third mode, the output signal is based on a signal from a third microphone arrangement.

20. A method according to claim 15, comprising:

obtaining an output from a sensor; and

determining, based on the sensor output, whether the apparatus is to operate in the first mode or in a third mode wherein, in the third mode, the output signal is based on a signal from a third microphone arrangement.

21. A method according to claim 15, comprising:

receiving the third signal from a telecommunications network.