Method and device for processing an audio signal in a vehicle

• US 10,785,566 B2
• Filed: 08/28/2019
• Issued: 09/22/2020
• Est. Priority Date: 12/05/2018
• Status: Active Grant

• Current Assignee: Baidu Online Network Technology (Beijing) Co., Ltd (Baidu Incorporated)
• Original Assignee: Baidu Online Network Technology (Beijing) Co., Ltd (Baidu Incorporated)
• Inventors: Geng, Lei
• Primary Examiner(s): Yu, Norman
• Application Number:
  US16/554,222
• Publication Number:
  US 20200186920A1
• Time in Patent Office: 391 Days
• Field of Search: 381 86, 381303, 381 714, 381 92, 381 26
• CPC Class Codes: B60R 11/0247 for microphones or earphones
• 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: G10L 21/0216 characterised by the method used for estimating noise
• CPC Class Codes: H04R 1/406 microphones
• CPC Class Codes: H04R 2201/401 2D or 3D arrays of transducers
• CPC Class Codes: H04R 2430/20 Processing of the output signals of the acoustic transducers of an array for obtaining a desired directivity characteristic H04R2203/12 takes precedence
• CPC Class Codes: H04R 2499/13 Acoustic transducers and sound field adaptation in vehicles
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407
• CPC Class Codes: H04R 3/04 for correcting frequency response
• CPC Class Codes: H04R 5/027 Spatial or constructional arrangements of microphones, e.g. in dummy heads
• CPC Class Codes: H04R 5/04 Circuit arrangements, e.g. for selective connection of amplifier inputs/outputs to loudspeakers, for loudspeaker detection, or for adaptation of settings to personal preferences or hearing impairments combinations of amplifiers H03F3/68; stereophonic systems H04S

Abstract

A method and a device for processing an audio signal in a vehicle are provided. The method includes: obtaining an audio signal by a microphone array; performing echo cancellation on the obtained audio signal, to obtain a first processed signal; and performing beamforming on the first processed signal according to sound zones in which microphones of the microphone array are located, to obtain a second processed signal, wherein the vehicle includes at least two sound zones, and each microphone of the microphone array is located in at least one sound zone. With the beamforming, the requirements for isolation degree between different sound zones is not high, and the sound source of the audio signal can be accurately determined.

Claims

1. A method for processing an audio signal in a vehicle, comprising:

obtaining an audio signal by a microphone array;

performing echo cancellation on the audio signal, to obtain a first processed signal;

performing beamforming on the first processed signal according to sound zones in which microphones of the microphone array are located, to obtain a second processed signal, wherein the vehicle comprises at least two sound zones, and each microphone of the microphone array is located in at least one sound zone; and

for each microphone of the microphone array;

determining a location of a sound source of the audio signal received by the microphone, to determine a sound zone in which the sound source is located;

comparing the determined sound zone with the sound zone in which the microphone is located, to determine whether the determined sound zone is identical with the sound zone in which the microphone is located; and

in a case that the determined sound zone is not identical with the sound zone in which the microphone is located, calibrating the sound zone in which the microphone is located by the determined sound zone.

2. The method according to claim 1, further comprising:

performing noise reduction and signal amplification on the second processed signal, to obtain a third processed signal; and

sending the third processed signal to an on-board operation system of the vehicle, to control the vehicle in response to the third processed signal.

3. The method according to claim 1, further comprising:

setting the sound zones in which respective microphones of the microphone array is located, based on a topology of the microphone array.

4. The method according to claim 3, wherein setting the sound zones in which respective microphones of the microphone array is located, based on the topology of the microphone array comprises at least one of:

determining a first microphone as a microphone in common with the sound zones, setting a sound zone in which a second microphone is located to a first sound zone, and setting a sound zone in which a third microphone is located to a second zone, wherein the microphone array is a triangle comprising at least three microphones; and

determining each microphone of the microphone array to be located in at least one sound zone, wherein the microphone array is a polygon with more than 3 sides, a circle, or a matrix comprising a plurality of microphones.

5. The method according to claim 1, wherein the performing beamforming on the first processed signal according, to the sound zones in which microphones of the microphone array are located, comprises:

performing the beamforming on the first processed signal based on the sound zone in which each microphone of the microphone array is located and a time when each microphone receives the audio signal, to determine the sound zone in which the sound source of tee audio signal is located.

6. The method according to claim 2, wherein the sending the third processed signal to the on-board operation system of the vehicle, comprises:

sending the third processed signal to the on-board operation system of the vehicle via an Automotive Audio Bus.

7. A device for processing an audio signal in a vehicle, comprising:

one or more processors; and

a storage device configured for storing one or more programs, wherein

the one or more programs are executed by the one or more processors to enable the one or more processors to;

obtain an audio signal by a microphone array;

perform echo cancellation on the audio to obtain a first processed signal;

perform beamforming on the first processed signal according to sound zones in which microphones of the microphone array are located, to obtain a second processed signal, wherein the vehicle comprises at least two sound zones, and each microphone of the microphone array is located in at least one sound zone; and

for each microphone of the microphone array,

determine a location of a sound source of the audio signal received by the microphone, to determine a sound zone in which the sound source is located;

compare the determined sound zone with the sound zone in which the microphone is located, to determine whether the determined sound zone is identical with the sound zone in which the microphone is located; and

in a case that the determined sound zone is not identical with the sound zone in which the microphone is located, calibrate the sound zone in which the microphone is located by the determined sound zone.

8. The device according to claim 7, wherein the one or more programs are executed by the one or more processors to enable the one or more processors further to:

perform noise reduction and signal amplification on the second processed signal, to obtain a third processed signal; and

send the third processed signal to an on-board operation system of the vehicle, to control the vehicle in response to the third processed signal.

9. The device according to claim 7, wherein the one or more programs are executed by the one or more processors to enable the one or more processors further to:

set the sound zones in which respective microphones of the microphone array is located, based on a topology of the microphone array.

10. The device according to claim 9, wherein the one or more programs are executed by the one or more processors to enable the one or more processors further to set the sound zones in which respective microphones of the microphone array is located based on the topology of the microphone array by at least one of:

determining a first microphone as a microphone in common with the sound zones, setting a sound zone in which a second microphone is located to a first sound zone, and setting a sound zone in which a third microphone is located to a second zone, wherein the microphone array is a triangle comprising at least three microphones; and

determining each microphone of the microphone array to be located in at least one sound zone, wherein the microphone array is a polygon with more than 3 sides, a circle, or a matrix comprising a plurality of microphones, and N is an integer greater than 3.

11. The device according to claim 7, wherein the one or more programs are executed by the one or more processors to enable the one or more processors further to:

perform the beamforming on the first processed signal based on the sound zone in which each microphone of the microphone array is located and a time when each microphone receives the audio signal, to determine the sound zone in which the sound source of the audio signal is located.

12. The device according to claim 8, wherein the one or more programs are executed by the one or more processors to enable the one or more processors further to send the third processed signal to the on-board operation system of the vehicle via an Automotive Audio Bus.

13. A non-transitory computer-readable storage medium, in which a computer program is stored, wherein the program, when executed by a processor, causes a vehicle to:

obtain an audio signal by a microphone array;

perform echo cancellation on the audio signal, to obtain a first processed signal;

perform beamforming on the first processed signal according to sound zones in which microphones of the microphone array are located, to obtain a second processed signal, wherein the vehicle comprises at least two sound zones, and each microphone of the microphone array is located in at least one sound zone; and

for each microphone of the microphone array,

determine a location of a sound source of the audio signal received by the microphone, to determine a sound zone in which the sound source is located;

compare the determined sound zone with the sound zone in which the microphone is located, to determine whether the determined sound zone is identical with the sound zone in which the microphone is located; and

in a case that the determined sound zone is not identical with the sound zone in which the microphone is located, calibrate the sound zone in which the microphone is located by the determined sound zone.

14. The non-transitory computer-readable storage medium according to claim 13, wherein, when executed, the program causes the vehicle further to:

perform noise reduction and signal amplification on the second processed signal, to obtain a third processed signal; and

send the third processed signal to an on-board operation system of the vehicle, to control the vehicle in response to the third processed signal.

15. The non-transitory computer-readable storage medium according to claim 14, wherein, when executed, the program causes the vehicle further to, when sending the third processed signal to the on-board operation system of the vehicle, send the third processed signal to the on-board operation system of the vehicle via an Automotive Audio Bus.

16. The non-transitory computer-readable storage medium according to claim 13, wherein, when executed, the program causes the vehicle further to set the sound zones in which respective microphones of the microphone array is located, based on a topology of the microphone array.

17. The non-transitory computer-readable storage medium according to claim 13, wherein the microphone array is a triangle comprising at least three microphones, and wherein, when executed, the program causes the vehicle further to, when setting the sound zones in which respective microphones of the microphone array is located:

setting a sound zone in which a first microphone and a second microphone are located to a first sound zone; and

setting a sound zone in which the first microphone and a third microphone are located to a second zone.

18. The non-transitory computer-readable storage medium according to claim 13, wherein each microphone of the microphone array is located in at least one sound zone, wherein the microphone array is a polygon with more than 3 sides, a circle, or a matrix comprising a plurality of microphones.