PASSENGER COMPARTMENT COMMUNICATION SYSTEM

• US 20100189275A1
• Filed: 01/25/2010
• Published: 07/29/2010
• Est. Priority Date: 01/23/2009
• Status: Active Grant

• Current Assignee: Harman Becker Automotive Systems GmbH (Samsung Electronics Co. Ltd.)
• Original Assignee: Harman Becker Automotive Systems GmbH (Samsung Electronics Co. Ltd.)
• Inventors: Christoph, Markus
• Granted Patent: US 8,824,697 B2
• Time in Patent Office: Days
• US Class Current: 381/66
• CPC Class Codes: H04R 2201/403 Linear 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 2430/23 Direction finding using a sum-delay beam-former
• 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 3/12 for distributing signals to two or more loudspeakers specially adapted for hearing aids H04R25/407

Abstract

A communication system for a passenger compartment includes at least two microphone arrays arranged within first and second regions, respectively, in the passenger compartment, and at least two loudspeakers and a signal processor connected to the microphone arrays and to the loudspeaker. Each microphone array has at least two microphones and provides an audio signal. Each loudspeaker is located within a different one of the first and the second regions. The signal processor processes the audio signal from the microphone array within the first region and provides the processed audio signal to the loudspeaker located within the second region.

Claims

1. A communication system for a passenger compartment, comprising:

at least two microphone arrays respectively arranged within first and second regions in the passenger compartment, where each microphone array has at least two microphones and is operable to provide a detected audio signal, and where the first region is different than the second region;

at least two loudspeakers, where each loudspeaker is located within a different one of the first and the second regions; and

a signal processor connected to the microphone arrays and to the loudspeakers, where the signal-processor processes the detected audio signals and to provide the processed audio signal to the loudspeaker located within the second region.

2. The system of claim 1, where

the signal processor includes at least two switching units, one of which is connected between the microphone array within the first region and the loudspeaker located within the second region, and the other of which is connected between the microphone array within the second region and the loudspeaker located within the first region;

and

the switching units are adapted to detect voice signal components in the detected audio signals from the microphones, and to selectively output those audio signals which include a voice signal component that is greater than a predetermined threshold value.

3. The system of claim 2, where each switching unit combines the detected audio signals that include the voice signal components that are greater than the predefined threshold value, and to output the combined signal.

4. The system of claim 3, where

the switching units weight the audio signals according to the strengths of their voice signal components, and to combine the audio signals based on their weights.

5. The system of claim 1, where the signal processor includes at least two processing units adapted to respectively perform beamforming using the detected audio signals to reduce noise in the audio signals.

6. The system of claim 1, where

the passenger compartment is the passenger compartment of a motor vehicle having at least four sitting positions;

the at least two microphone arrays include four microphone arrays, one microphone array being assigned to a front left sitting position, one microphone array being assigned to a front right sitting position, one microphone array being assigned to a rear left sitting position, and one microphone array being assigned to a rear right sitting position.

7. The system of claim 6, where the signal-processing arrangement includes four switching units, one of which is connected to the microphone array assigned to the front left sitting position, one of which is connected to the microphone array assigned to the front right sitting position, one of which is connected to the microphone array assigned to the rear left sitting position, and one of which is connected to the microphone array assigned to the rear right sitting position.

8. The system of claim 6, where the at least two loudspeakers include at least four loudspeakers, one of which is arranged proximate to the front left sitting position, one of which is arranged proximate to the front right sitting position, one of which is arranged proximate to the rear left sitting position, and one of which is arranged proximate to the rear right sitting position.

9. The system of claim 1, where the signal processor comprises at least one of the following units:

a noise level determination unit;

an acoustic echo suppression unit;

a DVC/DEC unit; and

an electric echo suppression unit.

10. The system of claim 8, where

the signal processing arrangement includes first and second DVC/DEC units, first and second noise level determination signal-processing units, and first and second echo suppression units;

the first DVC/DEC unit receives a noise level signal from the second noise level determination unit for a rear region of the passenger compartment as a reference signal, uses dynamic volume control and/or frequency equalization control processing to adapt the processed audio signal corresponding to the front region with regard to at least one of volume and frequency response, and to supply a corresponding first conditioned audio signal as an input signal to the loudspeakers located proximate to the rear left and rear right sitting positions and as a reference signal to the second echo suppression signal-processing unit; and

the second DVC/DEC unit receives a noise level signal from the first noise level determination unit for a front region of the passenger compartment as a reference signal, uses dynamic volume control and/or frequency equalization control processing to adapt the processed audio signal corresponding to the rear region with regard to at least one of volume and frequency response, and to supply a corresponding second conditioned audio signal as an input signal to the loudspeakers arranged proximate to the rear left and rear right sitting positions and as a reference signal to the first echo suppression signal-processing unit.

11. The system of claim 8, where

the signal processing arrangement includes first and second DVC/DEC units, and first and second summing elements;

the first DVC/DEC unit receives a noise level signal from a second noise level determination signal-processing unit for a rear region of the passenger compartment as a reference signal, and uses dynamic volume control and/or frequency equalization control processing to adapt the processed audio signal corresponding to the front region with regard to at least one of volume and frequency response, and to supply a corresponding first output signal as a first input signal to the second summing element; and

the second DVC/DEC unit receives a noise level signal from a first noise level determination signal-processing unit for a front region of the passenger compartment as a reference signal, and uses dynamic volume control and/or frequency equalization control processing to adapt the processed audio signal corresponding to the rear region with regard to at least one of volume and frequency response, and supplies a corresponding second output signal as a first input signal to the first summing element.

12. The system of claim 11, further comprising at least one signal source that provides a source signal, in which

a third DVC/DEC unit receives a source signal from the signal source, and uses the noise level signal from the first noise level determination unit for the front region of the passenger compartment as a reference signal, to use dynamic volume control and/or frequency equalization control processing to adapt the source signal with regard to at least one of volume and frequency response, and to supply a corresponding processed source signal as a second input signal to the first summing element;

a fourth signal-processing unit that receives the source signal from the signal source, uses the noise level signal from the second noise level determination unit for the rear region of the passenger compartment as a reference signal, and uses dynamic volume control and/or frequency equalization control processing to adapt the source signal with regard to at least one of volume and frequency response, and to supply a corresponding processed source signal as a second input signal to the second summing element;

the first summing element adds the first and the second input signals, and supplies a resulting sum signal as an input signal for the loudspeakers arranged proximate to the rear left and rear right sitting positions and as a reference signal to a first echo suppression signal-processing unit; and

the second summing element adds the first and the second input signals, and supplies a resulting sum signal as an input signal to the loudspeakers arranged proximate to the rear left and rear right sitting positions and as a reference signal to a second echo suppression signal-processing unit.

13. The system of claim 11, further comprising a multimedia signal source;

a telephone signal source that provides a source signal;

a third switching unit; and

a third summing element, in which

the third summing element provides a sum signal by adding the source signal and the telephony signal;

a third DVC/DEC unit that receives the sum signal from the third summing element, to use the noise level signal from the first noise level determination unit for the front region of the passenger compartment as a reference signal, to use dynamic volume control and/or frequency equalization control processing to adapt the sum signal with regard to at least one of volume and frequency response, and to supply a corresponding first processed source signal as a second input signal to the first summing element;

a fourth DVC/DEC unit is that receives the sum signal from the third summing element, to use the noise level signal from the second noise level determination signal-processing unit for the rear region of the passenger compartment as a reference signal, to use dynamic volume control and/or frequency equalization control processing to adapt the sum signal with regard to at least one of volume and frequency response, and to supply a corresponding second processed source signal as a second input signal to the second summing element;

the first summing element adds the first and the second input signals, and to supply a resulting sum signal as an input signal to the loudspeakers arranged proximate to the rear left and rear right sitting positions and as a reference signal to the first echo suppression unit; and

the second summing element is adapted to add the first and the second input signals, and to supply a resulting sum signal as an input signal to the loudspeakers arranged proximate to the rear left and rear right sitting positions and as a reference signal to the second echo suppression unit;

the third switching unit is adapted to receive the output signals from the first and the second DVC/DEC signal-processing units, and to transmit the output signals from the first and the second DVC/DEC units which include a voice signal component whose is greater than a predetermined threshold value.

14. A method for improving voice communication in an environment subject to interference, comprising:

providing at least four microphone arrays arranged in the environment, each microphone array including at least two microphones, where a first one of the microphone arrays is disposed within a first region;

providing at least four signal-processing arrangements, where each signal-processing arrangement receives at least two audio signals from a respective one of the microphone arrays;

respectively processing the received audio signals using the signal-processing arrangements to provide corresponding processed output signals; and

supplying one of the processed output signals from the first one of the microphone arrays to a first one of a plurality of loudspeakers that is disposed within a second region;

where the first region is different than the second region.

15. The method of claim 14, further comprising:

providing at least two switching units, where each switching unit receives audio signals from two of the microphone arrays;

detecting, via the switching units, one or more voice signal components in one or more of the received audio signals;

comparing the voice signal components to a threshold value; and

respectively outputting, from the switching units, the received audio signals that include the voice signal components that are greater than the threshold value.

16. The method of claim 15, further comprising providing a sum signal for each switching unit that receives two or more audio signals that include the voice signal components that are greater than the threshold value, where the step of respectively outputting outputs the summed signal.

17. The method of claim 16, further comprising:

providing two or more weighted signals for each switching unit that receives two or more processed output signals that include the voice signal components that are greater than the threshold value, where these processed output signals are weighted as a function of their voice signal component strengths; and

adding the weighted signals together to provide the summed signal for a respective one of the switching units.

18. The method of claim 15, further comprising beamforming with the received audio signals for each respective microphone arrays using the signal-processing arrangements for reducing noise in the received signals.

19. The method of claim 15, where the environment comprises a passenger compartment of a motor vehicle.

20. The method of claim 19, where one of the microphone arrays is arranged within a front left region of the passenger compartment, another one of the microphone arrays is arranged within a front right of the passenger compartment, another one of the microphone arrays is arranged within a rear left region of the passenger compartment, and another one of the microphone arrays is arranged within a rear right region of the passenger compartment.

21. The method of claim 20, where at least two signal-processing arrangements and at least one switching unit are configured in communication with the front left and the front right microphone arrays, where at least two signal-processing arrangements and at least one switching unit are configured in communication with the rear left and the rear right microphone arrays, where one of the switching units provides a sum signal for a front region of the passenger compartment, and where the other one of the switching units provides a sum signal for a rear region of the passenger compartment.

22. The method of claim 21, where one loudspeaker is arranged front left in the passenger compartment, where another loudspeaker is arranged front right in the passenger compartment, where another loudspeaker is arranged rear left in the passenger compartment, and where another loudspeaker is arranged rear right in the passenger compartment, where the method further comprises:

receiving the audio signals from the front left microphone array and the audio signals from the front right microphone array at a noise level detection signal-processing unit for the front region to determine a front noise signal level;

receiving the audio signals from the rear left microphone array and the audio signals from the rear right microphone array at a noise level detection signal-processing unit for the rear region to determine a rear noise signal level;

determining averaged, resulting noise signal levels for at least one of the front and the rear regions of the passenger compartment respectively using the audio signals;

receiving the sum signal for the front region of the passenger compartment at a front echo suppression signal-processing unit;

receiving the sum signal for the rear region of the passenger compartment at a rear echo suppression signal-processing unit;

suppressing acoustic echoes in the sum signal, via the front echo suppression signal-processing unit, for the front region of the passenger compartment using an Automatic Equalizing Control algorithm, and providing a front suppressed signal to a front DVC/DEC signal-processing unit; and

suppressing acoustic echoes in the sum signal, via the rear echo suppression signal-processing unit, for the rear region of the passenger compartment using an Automatic Equalizing Control algorithm, and providing a rear suppressed signal to a rear DVC/DEC signal-processing unit.

23. The method of claim 21, further comprising:

adapting the sum signal from the switching unit for the front region of the passenger compartment with regard to at least one of volume and frequency response using dynamic volume control and/or frequency equalization control algorithms, and providing the adapted signal to the loudspeakers arranged within the rear region and to a rear echo suppression signal-processing unit as a reference signal; and

adapting the sum signal from the switching unit for the rear region of the passenger compartment with regard to at least one of volume and frequency response using dynamic volume control and/or frequency equalization control algorithms, and providing the adapted signal to the loudspeakers arranged within the front region and to a front echo suppression signal-processing unit as a reference signal.

24. The method of claim 21, further comprising:

adapting the signal from the switching unit for the front region of the passenger compartment with regard to at least one of volume and frequency response using dynamic volume control and/or frequency equalization control algorithms, and providing the adapted signal to a summing element for the rear region of the passenger compartment as a first input signal; and

adapting the signal from the switching unit for the rear region of the passenger compartment with regard to at least one of volume and frequency response using dynamic volume control and/or frequency equalization control algorithms, and providing the adapted signal to a summing element for the front region of the passenger compartment as a first input signal.

25. The method of claim 22, further comprising:

receiving a source signal from a signal source and the averaged, resulting noise signal level for the front region as a reference signal, and adapting the source signal with regard to at least one of volume and/or frequency response using dynamic volume control and/or frequency equalization control algorithms, and supplying the adapted source signal as a second input signal to a front summing element;

receiving the source signal from the signal source and the averaged, resulting noise signal level for the rear region as a reference signal, and adapting the source signal with regard to at least one of volume and frequency response using dynamic volume control and/or frequency equalization control algorithms, and supplying the adapted source signal as a second input signal to a rear summing element;

adding, via the front summing element, an output signal from the rear DVC/DEC signal-processing unit and the second input signal, and supplying a resulting sum signal as an input signal for the front left and the front right loudspeakers and as a reference signal for the front echo suppression signal-processing unit; and

adding, via the rear summing element, an output signal from the front DVC/DEC signal-processing unit and the second input signal, and supplying the resulting sum signal as an input signal for the rear left and the rear right loudspeakers and as a reference signal for the rear echo suppression signal-processing unit.

26. The method of claim 22, further comprising:

adding output signals from a signal source and a telephone signal source, and supplying a corresponding sum signal via a summing element;

receiving the sum signal from the summing element and the averaged, resulting noise signal level for the front region as a reference signal, adapting the sum signal with regard to at least one of volume and frequency response using dynamic volume control and/or frequency equalization control algorithms, and supplying the adapted source signal as a second input signal to a front summing element;

receiving the sum signal from the summing element and the averaged, resulting noise signal level for the rear region as a reference signal, adapting the sum signal with regard to at least one of volume and frequency response using dynamic volume control and/or frequency equalization control algorithms, and supplying the adapted source signal as a second input signal to a rear summing element;

adding, via the front summing element, an output signal from the rear DVC/DEC signal-processing unit and the second input signal, and supplying a resulting sum signal as an input signal to the front left and the front right loudspeakers and as a reference signal for the front echo suppression signal-processing unit;

adding, via the rear summing element, an output signal from the front DVC/DEC signal-processing unit and the second input signal, and supplying a resulting sum signal as an input signal to the rear left and the rear right loudspeakers and as a reference signal for the rear echo-suppression signal-processing unit;

receiving the output signals from the front and the rear DVC/DEC signal-processing units at a switching unit; and

outputting the output signals from the front and the rear DVC/DEC signal-processing units that include a voice signal component that is greater than a predetermined threshold value.

27. A communication system for a passenger compartment of a motor vehicle, the system comprising:

first and second microphone arrays, each microphone array including a plurality of microphones, the first microphone array provides a plurality of first audio signals and is located within a first region, and the second microphone array provide a plurality of second audio signals and is located within a second region, where the first region is different than the second region;

first and second loudspeakers, the first loudspeaker being located within the first region, and the second loudspeaker being located within the second region; and

a signal processor that receives the first and the second audio signals, and provides a first conditioned audio signal derived from the first audio signal to the second loudspeaker.

28. The communication system of claim 27, where the first region surrounds a driver seat, and where the second region surrounds a passenger seat.

29. The communication system of claim 27, where the signal processor includes first and second beamforming and noise suppression processing units, the first beamforming and noise suppression processing unit provides a first beamformed signal derived from at least one of the first audio signals, and the second beamforming and noise suppression processing unit provides a second beamformed signal derived from at least one of the second audio signals.

30. The communication system of claim 29, further comprising:

third and fourth microphone arrays, each including a plurality of microphones, where the third microphone array provides a plurality of third audio signals and is located within a third region, and the fourth microphone provides a plurality of fourth audio signals and is located within a fourth region; and

third and fourth loudspeakers, the third loudspeaker being disposed within the third region, and the fourth loudspeaker being disposed within the fourth region;

where the signal processor includes third and fourth beamforming and noise suppression processing units, where the third beamforming and noise suppression processing unit provides a third beamformed signal derived from at least one of the third audio signals, and the fourth beamforming and noise suppression processing unit provides a fourth beamformed signal derived from at least one of the fourth audio signals.

31. The communication system of claim 30, where the signal processor comprises:

first and second detection and weighting units, the first detection and weighting unit selectively provide a first output signal derived from at least one of the first and the second beamformed signals when at least one of the first and the second beamformed signals includes a voice signal component that is greater than a first threshold value, and the second detection and weighting unit selectively provides a second output signal derived from at least one of the third and the fourth beamformed signals when at least one of the third and the fourth beamformed signals includes a voice signal component that is greater than a second threshold value.

32. The communication system of claim 31, where the signal processor comprises:

first and second echo suppression units, where the first echo suppression unit provides a first suppressed signal derived from the first output signal and a second reference signal, and the second echo suppression unit provides a second suppressed signal derived from the second output signal and a first reference signal.

33. The communication system of claim 31, where the signal processor comprises:

first and second noise level detection units, where the first noise level detection unit provides a first noise level signal derived from at least one of the first audio signals and at least one of the second audio signals, and the second noise level detection unit provides a second noise level signal derived from at least one of the third audio signals and at least one of the fourth audio signals; and

first and second DVC/DEC processing units, where the first DVC/DEC processing unit provides a first processed signal derived from the first output signal and the second noise level signal, and the second DVC/DEC processing unit provides a second processed signal derived from the second output signal and the first noise level signal.

34. A method for improving voice communication in an environment subject to interference, comprising:

detecting sound in a first region of the environment via a first array of microphones to provide a plurality of first audio signals;

detecting sound in a second region of the environment via a second array of microphones to provide a plurality of second audio signals;

processing at least one of the first audio signal to provide a first conditioned signal and the second audio signals to provide a second conditioned signal via a signal processing arrangement; and

selectively reproducing at least one of the first conditioned signal in the second region of the environment via a second loudspeaker and the second conditioned signal in the first region of the environment via a first loudspeaker.

35. The method of claim 34, where the step of processing comprises:

beamforming and suppressing noise for the first audio signals to provide a first beamformed signal; and

beamforming and suppressing noise for the second audio signals to provide a second beamformed signal;

36. The method of claim 35, where the step of processing further comprises:

detecting sound in a third region of the environment via a third array of microphones to provide a plurality of third audio signals;

detecting sound in a fourth region of the environment via a fourth array of microphones to provide a plurality of fourth audio signals;

beamforming and suppressing noise for the third audio signals to provide a third beamformed signal; and

beamforming and suppressing noise for the fourth audio signals to provide a fourth beamformed signal.

37. The method of claim 36, where the step of processing further comprises:

selectively providing a first output signal derived from at least one of the first and the second beamformed signals when at least one of the first and the second beamformed signals includes a voice signal component that is greater than a first threshold value; and

selectively providing a second output signal derived from at least one of the third and the fourth beamformed signals when at least one of the third and the fourth beamformed signals includes a voice signal component that is greater than a second threshold value.

38. The method of claim 35, where the step of processing further comprises:

providing a first suppressed signal derived from the first beamformed signal and a second reference signal; and

providing a second suppressed signal derived from the second beamformed signal and a first reference signal.

39. The method of claim 35, where the step of processing further comprises:

applying dynamic volume control and/or frequency equalization control processing to the first beamformed signal using a second noise level signal as a reference signal to provide a first processed signal; and

applying dynamic volume control and/or the frequency equalization control processing to the second beamformed signal using a first noise level signal as a reference signal to provide a second processed signal.

40. The method of claim 37, where the step of processing further comprises:

applying dynamic volume control and/or frequency equalization control processing to the first output signal using a second noise level signal as a reference signal to provide a first processed signal; and

applying dynamic volume control and/or the frequency equalization control processing to the second output signal using a first noise level signal as a reference signal to provide a second processed signal;

providing a source signal derived from at least one of an audio system and a communication system;

applying dynamic volume control and/or frequency equalization control processing to the source signal using the first noise level signal as a reference signal to provide a third processed signal;

applying dynamic volume control and/or frequency equalization control processing to the source signal using the second noise level signal as a reference signal to provide a fourth processed signal;

adding the second processed signal and the third processed signal to provide the second conditioned signal; and

adding the first processed signal and the fourth processed signal to provide the first conditioned signal.