ARRAY MICROPHONE AND SOUND COLLECTION METHOD

• US 20200137485A1
• Filed: 10/21/2019
• Published: 04/30/2020
• Est. Priority Date: 10/24/2018
• Status: Active Grant

• Current Assignee: Yamaha Corporation
• Original Assignee: Yamaha Corporation
• Inventors: YAMAKAWA, Takashi, IKEGAYA, Yuji
• Granted Patent: US 10,869,123 B2
• Time in Patent Office: Days
• CPC Class Codes: G10L 2021/02082 the noise being echo, reverberation of the speech
• CPC Class Codes: G10L 2021/02166 Microphone arrays; Beamforming
• CPC Class Codes: G10L 21/0208 Noise filtering
• CPC Class Codes: H04M 9/082 using echo cancellers echo cancellers per se H04B3/23
• CPC Class Codes: H04R 1/406 microphones
• CPC Class Codes: H04R 2201/401 2D or 3D arrays of transducers
• CPC Class Codes: H04R 2430/23 Direction finding using a sum-delay beam-former
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407

Abstract

A sound collection method includes estimating at least one sound source direction and forming a plurality of sound collection beams in the estimated plurality of sound source direction, using sound collection signals of a plurality of microphones. The number of sound source directions estimated is smaller than the number of sound collection beams formed.

Claims

1. An array microphone comprising:

a plurality of microphones;

an estimator that estimates at least one sound source direction; and

a beam former that forms a plurality of sound collection beams in the estimated at least one sound source directions, using sound collection signals of the plurality of microphones,

wherein a number of the at least one sound source direction estimated by the estimator is smaller than a number of sound collection beams formed by the beam former.

2. The array microphone according to claim 1, further comprising a mixing processor that mixes an audio signal according to a sound collection beam, among the plurality of sound collection beams, by a gain according to volume of the sound collection beam.

3. The array microphone according to claim 1, wherein the plurality of microphones are arranged in a plane.

4. The array microphone according to claim 1, wherein the plurality of microphones are configured as a ceiling tile.

5. The array microphone according to claim 4, wherein the ceiling tile is configured to be replaceable.

6. The array microphone according to claim 1, further comprising an echo canceller that removes an echo component from an audio signal according to a sound collection beam, among the plurality of sound collection beams.

7. The array microphone according to claim 1, further comprising:

an echo canceller that removes an echo component from the plurality of sound collection signals of the plurality of microphones,

wherein the estimator estimates each sound source direction, using the sound collection signals in which the echo component has been removed by the echo canceller.

8. The array microphone according to claim 1, wherein:

a first sound collection direction of at least one sound collection beam, among the plurality of sound collection beams, is fixed, and

a second sound collection direction of at least one sound collection beam, among the plurality of sound collection beams, is determined based on the sound source direction thereof that has been estimated by the estimator.

9. The array microphone according to claim 1, wherein the beam former forms one sound collection beam, among the plurality of sound collection beams, for each predetermined area.

10. The array microphone according to claim 9, wherein the beam former:

records an estimated frequency of the sound source direction for each area; and

forms the one sound collection beam according to the estimated frequency.

11. A sound collection method comprising:

one or more processors and memory storing one or more programs for execution by the one or more processors;

estimating at least one sound source direction; and

forming a plurality of sound collection beams in the estimated at least one sound source directions, using sound collection signals of a plurality of microphones,

wherein a number of sound source directions to be estimated is smaller than a number of sound collection beams to be formed.

12. The sound collection method according to claim 11, further comprising mixing an audio signal according to a sound collection beam, among the plurality of sound collection beams, by a gain according to volume of the sound collection beam.

13. The sound collection method according to claim 11, wherein the plurality of microphones are configured as a ceiling tile.

14. The sound collection method according to claim 13, wherein the ceiling tile is configured to be replaceable.

15. The sound collection method according to claim 11, further comprising removing an echo component from an audio signal according to a sound collection beam, among the plurality of sound collection beams.

16. The sound collection method according to claim 15, further comprising:

removing an echo component from the plurality of sound collection signals of the plurality of microphones,

wherein the estimating of the plurality of sound source directions estimates each sound source direction, using the sound collection signals in which the echo component has been removed.

17. The sound collection method according to claim 11, wherein

a first sound collection direction of at least one sound collection beam, among the plurality of sound collection beams is fixed, and

a second sound collection direction of at least one sound collection beam, among the plurality of sound collection beams, is determined based on the sound source direction thereof that has been estimated.

18. The sound collection method according to claim 11, wherein the forming of the plurality of sound collection beams forms one sound collection beam, among the plurality of the sound collection beams, for each predetermined area.

19. The sound collection method according to claim 18, wherein the forming of the plurality of sound collection beams:

records an estimated frequency of the sound source direction for each area; and

forms the one sound collection beam according to the estimated frequency.

20. An array microphone comprising:

a plurality of microphones;

one or more processors; and

one or more memories having program instructions stored thereon that are executable by the one or more processors to cause the array microphone to;

estimate at least one sound source direction; and

form a plurality of sound collection beams in the estimated at least one sound source directions, using sound collection signals to be collected by the plurality of microphones,

wherein a number of sound source directions to be estimated is smaller than a number of sound collection beams to be formed.