POSITION DIRECTED ACOUSTIC ARRAY AND BEAMFORMING METHODS

• US 20140372129A1
• Filed: 06/14/2013
• Published: 12/18/2014
• Est. Priority Date: 06/14/2013
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: TZIRKEL-HANCOCK, ELI, BILIK, IGAL, LAIFENFELD, MOSHE
• Granted Patent: US 9,747,917 B2
• Time in Patent Office: Days
• US Class Current: 704/278
• CPC Class Codes: G01S 13/06 Systems determining position data of a target
• CPC Class Codes: G01S 15/06 Systems determining the position data of a target
• CPC Class Codes: G10L 15/00 Speech recognition G10L17/00 takes precedence
• CPC Class Codes: G10L 2021/02166 Microphone arrays; Beamforming
• CPC Class Codes: G10L 21/00 Speech or voice signal processing techniques to produce another audible or non-audible signal, e.g. visual or tactile, in order to modify its quality or its intelligibility G10L19/00 takes precedence
• CPC Class Codes: G10L 21/0208 Noise filtering
• CPC Class Codes: H04R 2201/401 2D or 3D arrays of transducers
• CPC Class Codes: H04R 2201/405 Non-uniform arrays of transducers or a plurality of uniform arrays with different transducer spacing
• CPC Class Codes: H04R 2430/25 Array processing for suppression of unwanted side-lobes in directivity characteristics, e.g. a blocking matrix
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407

Abstract

Methods and systems are provided for receiving desired sounds. The system includes a position sensor configured to determine an occupant position of an occupant engaging in speech within a defined space and transmit the speaking occupant position. A plurality of microphones are configured to receive sound from within the defined space and transmit audio signals corresponding to the received sound. A processor, in communication with the position sensor and the microphones, is configured to receive the speaking occupant position and the audio signals, apply a beamformer to the audio signals to direct a microphone beam toward the occupant position, and generate a beamformer output signal.

Claims

1. An adaptive beamforming method for receiving desired sounds, said method comprising:

determining an occupant position of an occupant engaging in speech within a defined space;

receiving sound from within the defined space with a plurality of microphones;

generating a plurality of audio signals corresponding to the received sound at each of said plurality of microphones; and

applying a beamformer to the audio signals to direct a microphone beam toward the determined occupant position and generate a beamformer output signal.

2. A method as set forth in claim 1 further comprising:

applying a blocking matrix to each of the audio signals to exclude other positions not associated with the occupant engaging in speech and generate a plurality of blocking matrix output signals corresponding to each of the audio signals;

applying an adaptive noise cancellation process to the blocking matrix output signals to generate an adaptive noise cancellation output signal; and

summing the beamformer output signal and the adaptive noise cancellation output signal to generate a speaking occupant output signal.

3. A method as set forth in claim 1 further comprising sending the speaking occupant output signal to a speech recognition system.

4. A method as set forth in claim 1 further comprising sending the speaking occupant output signal to a telephony system.

5. A method as set forth in claim 1 wherein determining an occupant position comprises:

transmitting waves in at least one of an ultrasonic range and a radio frequency (RF) range with a plurality of transmitters;

receiving reflected waves; and

analyzing signals corresponding to the transmitted and reflected waves to determine the occupant position.

6. A method as set forth in claim 1 further comprising determining that an occupant is engaging in speech.

7. A method as set forth in claim 6 wherein determining that an occupant is engaging in speech comprises identifying motion of a mouth of the occupant engaging in speech by searching for distinguishing features in spatio-temporal and/or velocity features of signals corresponding to the reflected waves.

8. A method as set forth in claim 1 wherein determining an occupant position comprises analyzing seat sensor data from at least one seat sensor.

9. A system for receiving desired sounds, said system comprising:

a position sensor configured to determine an occupant position of an occupant engaging in speech within a defined space and transmit the speaking occupant position;

a plurality of microphones configured to receive sound from within the defined space and transmit audio signals corresponding to the received sound; and

a processor in communication with said position sensor and said microphones and configured to receive the speaking occupant position and the audio signals, apply a beamformer to the audio signals to direct a microphone beam toward the determined occupant position, and generate a beamformer output signal.

10. A system as set forth in claim 9 wherein said processor is also configured to apply a blocking matrix to each of the audio signals to exclude other positions not associated with the occupant engaging in speech to generate a plurality of blocking matrix output signals corresponding to each of the audio signals, apply an adaptive noise cancellation process to the blocking matrix output signals to generate an adaptive noise cancellation output signal, and sum the beamformer output signal and the adaptive noise cancellation output signal to generate a speaking occupant output signal.

11. A system as set forth in claim 9 wherein said position sensor comprises:

a signal generator;

a plurality of ultrasonic transmitters electrically coupled to said signal generator and configured to generate sound waves in the ultrasonic range;

a plurality of ultrasonic receivers for receiving reflected sound waves in the ultrasonic range and generating a plurality of received signals corresponding to the received reflected sound waves; and

a processing unit electrically coupled to said ultrasonic receivers and said processor and configured to receive the received signals, determine the occupant position, and provide the occupant position to said processor.

12. A system as set forth in claim 11 wherein said position sensor is configured to identify motion of a mouth of the occupant engaging in speech by searching for distinguishing features in spatio-temporal and/or velocity features of signals corresponding to the reflected sound waves.

13. A system as set forth in claim 9 wherein said position sensor comprises:

a signal generator;

a plurality of RF transmitters electrically coupled to said signal generator for generating RF waves in the RF range;

a plurality of RF receivers for receiving reflected RF waves in the RF range and generating a plurality of received signals corresponding to the received reflected RF waves; and

a processing unit electrically coupled to said RF receivers and said processor and configured to receive the received signals, determine the occupant position, and provide the occupant position to said processor.

14. A system as set forth in claim 13 wherein said position sensor is configured to identify motion of a mouth of the occupant engaging in speech by searching for distinguishing features in spatio-temporal and/or velocity features of signals corresponding to the reflected RF waves.

15. A system as set forth in claim 9 wherein said position sensor comprises a camera.

16. A vehicle comprising:

a passenger compartment;

an audio system comprising

a position sensor configured to determine an occupant position of an occupant engaging in speech within the passenger compartment and transmit the speaking occupant position;

a plurality of microphones configured to receive sound from within the defined space and transmit audio signals corresponding to the received sound;

a processor in communication with said position sensor and said microphones and configured to receive the speaking occupant position and the audio signals, apply a beamformer to the audio signals to direct a microphone beam toward the occupant position, and generate a beamformer output signal, apply a blocking matrix to each of the audio signals to exclude other positions not associated with the occupant engaging in speech to generate a plurality of blocking matrix output signals corresponding to each of the audio signals, apply an adaptive noise cancellation process to the blocking matrix output signals to generate an adaptive noise cancellation output signal, and sum the beamformer output signal and the adaptive noise cancellation output signal to generate a speaking occupant output signal; and

at least one of a speech recognition system and a telephony system in communication with said audio system for receiving said speaking occupant output signal.

17. A system as set forth in claim 16 wherein said position sensor comprises:

a signal generator;

a plurality of ultrasonic transmitters electrically coupled to said signal generator and configured to generate sound waves in the ultrasonic range;

a plurality of ultrasonic receivers for receiving reflected sound waves in the ultrasonic range and generating a plurality of received signals corresponding to the received reflected sound waves; and

a processing unit electrically coupled to said ultrasonic receivers and said processor and configured to receive the received signals, determine the occupant position, and provide the occupant position to said processor.

18. A system as set forth in claim 17 wherein said position sensor is configured to identify motion of a mouth of the occupant engaging in speech by searching for distinguishing features in spatio-temporal and/or velocity features of signals corresponding to the reflected sound waves.

19. A system as set forth in claim 16 wherein said position sensor comprises:

a signal generator;

a plurality of RF transmitters electrically coupled to said signal generator for generating RF waves in the RF range;

a plurality of RF receivers for receiving reflected RF waves in the RF range and generating a plurality of received signals corresponding to the received reflected RF waves; and

a processing unit electrically coupled to said RF receivers and said processor and configured to receive the received signals, determine the occupant position, and provide the occupant position to said processor.

20. A system as set forth in claim 19 wherein said position sensor is configured to identify motion of a mouth of the occupant engaging in speech by searching for distinguishing features in spatio-temporal and/or velocity features of signals corresponding to the reflected RF waves.