IN-CAR COMMUNICATION SYSTEM FOR MULTIPLE ACOUSTIC ZONES

• US 20130179163A1
• Filed: 01/10/2012
• Published: 07/11/2013
• Est. Priority Date: 01/10/2012
• Status: Active Grant

• Current Assignee: Cerence Operating Company (Cerence Inc.)
• Original Assignee: Nuance Communications, Inc. (Microsoft Corporation)
• Inventors: Herbig, Tobias, Buck, Markus, Pfeffinger, Meik
• Granted Patent: US 9,641,934 B2
• Time in Patent Office: Days
• US Class Current: 704/233
• CPC Class Codes: G10L 2021/02082 the noise being echo, reverberation of the speech
• CPC Class Codes: G10L 21/0208 Noise filtering
• CPC Class Codes: G10L 25/84 for discriminating voice from noise
• 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 2201/403 Linear arrays of transducers
• CPC Class Codes: H04R 2227/001 Adaptation of signal processing in PA systems in dependence of presence of noise
• CPC Class Codes: H04R 2227/009 Signal processing in [PA] systems to enhance the speech intelligibility
• CPC Class Codes: H04R 2410/05 Noise reduction with a separate noise microphone
• CPC Class Codes: H04R 2420/01 Input selection or mixing for amplifiers or loudspeakers for hearing aids H04R25/43
• CPC Class Codes: H04R 2499/13 Acoustic transducers and sound field adaptation in vehicles
• CPC Class Codes: H04R 27/00 Public address systems circuits for preventing acoustic reaction H04R3/02; circuits for distributing signals to loudspeakers H04R3/12; monitoring or testing arrangements for public address systems H04R29/007; amplifiers H03F
• 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 3/02 for preventing acoustic reaction , i.e. acoustic oscillatory feedback specially adapted for hearing aids H04R25/453
• CPC Class Codes: H04R 3/12 for distributing signals to two or more loudspeakers specially adapted for hearing aids H04R25/407
• CPC Class Codes: H04R 5/02 Spatial or constructional arrangements of loudspeakers

Abstract

An In-Car Communication (ICC) system supports the communication paths within a car by receiving the speech signals of a speaking passenger and playing it back for one or more listening passengers. Signal processing tasks are split into a microphone related part and into a loudspeaker related part. A sound processing system suitable for use in a vehicle having multiple acoustic zones includes a plurality of microphone In-Car Communication (Mic-ICC) instances coupled and a plurality of loudspeaker In-Car Communication (Ls-ICC) instances. The system further includes a dynamic audio routing matrix with a controller and coupled to the Mic-ICC instances, a mixer coupled to the plurality of Mic-ICC instances and a distributor coupled to the Ls-ICC instances.

Claims

1. A sound processing system suitable for use in a vehicle having a plurality of microphones and a plurality of loudspeakers distributed in multiple acoustic zones, the system comprising:

a plurality of microphone In-Car Communication (Mic-ICC) instances coupled to corresponding ones of the plurality of microphones;

a plurality of loudspeaker In-Car Communication (Ls-ICC) instances coupled to corresponding ones of the plurality of loudspeakers;

a dynamic audio routing matrix comprising;

a controller and coupled to the plurality of Mic-ICC instances;

a mixer coupled to the plurality of Mic-ICC instances; and

a distributor coupled to the plurality of Ls-ICC instances.

2. The system of claim 1, wherein the mixer comprises an input selector coupled to the controller;

wherein the distributor comprises an output selector coupled to the controller; and

wherein the plurality of Mic-ICC instances are coupled to the input selector; and

the plurality of Ls-ICC instances are coupled to the output selector.

3. The system of claim 1 further comprising a notch filter coupled to the mixer and the distributor.

4. The system of claim 1, wherein the plurality of microphones includes a microphone array and the plurality of Mic-ICC instances include beam forming processing.

5. The system of claim 1, wherein the number of acoustic zones is greater than two.

6. The system of claim 1, further comprising predetermined equalization parameters corresponding to the multiple acoustic zones and vehicle audio system.

7. The system of claim 1, further comprising an adaptive gain control to adjust playback level to compensate for current noise levels in the vehicle.

8. The system of claim 7, wherein the adaptive gain control adjusts a playback level for each Ls-ICC individually to compensate for current noise levels in the corresponding acoustic zone.

9. The system of claim 7, wherein the controller detects signal activity on the basis of the input signals and changes weights dynamically depending on signal activity.

10. A method for providing speech intelligibility in a vehicle having a plurality of microphones and a plurality of loudspeakers distributed in multiple acoustic zones, the method comprising:

processing speech from the plurality of microphones using a corresponding plurality of microphone In-Car Communication (Mic-ICC) instances;

analyzing signals from the plurality of Mic-ICC instances;

detecting speech and determining active acoustic paths;

calculating weights for the plurality of Mic-ICC instances based on speech and active acoustic paths;

applying the calculated weights to provide weighted audio signals; and

distributing the weighted audio signals to a plurality of loudspeaker ICC (Ls-ICC) instances coupled to corresponding ones of the plurality of loudspeakers.

11. The method of claim 10, further comprising:

detecting signal activity on the basis of the input signals; and

changing the weights dynamically depending on signal activity.

12. The method of claim 11, further comprising:

determining active acoustic paths; and

calculating equalizers only for the active acoustic paths.

13. The method of claim 10, further comprising:

mapping a plurality of input channels formed by the plurality of microphones and corresponding Mic-ICC instances to at least one selected channel; and

distributing the at least one selected channel signal from the at least one selected channel to the plurality of loudspeakers through the corresponding plurality of Ls-ICC instances.

14. The method of claim 13, wherein the at least one selected channel is a single channel.

15. The method of claim 13, further comprising selecting the at least one selected channel based on the calculated weights.

16. The method of claim 13, further comprising:

calculating a notch filter to reduce feedback; and

applying the notch filter to the at least one selected channel.

17. The method of claim 13, further comprising calculating N−

1 sets of equalizer coefficients where N equals the total number of Ls-ICC instances in the system.

18. The method of claim 17, further comprising distributing the filtered input to the plurality of Ls-ICC instances based on the calculated weights.

19. The method of claim 10, wherein a signal delay from the plurality of microphones to the plurality of loudspeakers distributed in multiple acoustic zones is less than about 10 ms.

20. The method of claim 10, wherein the number of acoustic paths is greater than two.

21. The method of claim 10, further comprising detecting speaker activity and determining active acoustic paths.

22. The method of claim 21, wherein detecting speaker activity and determining active acoustic paths comprises interfacing with an on-board computer via a CAN bus to determine whether there are passengers in various seats in the vehicle.

23. The method of claim 10, further comprising estimating the background noise level for each of the multiple acoustic zones.

24. The method of claim 23, further comprising separately adjusting a playback level in a distributor for each Ls-ICC as a function of estimated background noise level in corresponding ones of the multiple acoustic zones.

25. The method of claim 24, further comprising interfacing with on-board computer via a CAN bus to determine vehicle speed and adjusting the playback level for each Ls-ICC as a function of vehicle speed.

26. A sound processing system suitable for use in a vehicle, the system comprising:

a plurality of microphones distributed within the vehicle;

a plurality of loudspeakers distributed within the vehicle;

a plurality of microphone In-Car Communication (Mic-ICC) processors operable to receive a microphone output from corresponding ones of the plurality of microphones and process respective Mic-ICC outputs;

a dynamic audio routing matrix operable to receive and process the respective processed microphone outputs from each of plurality of Mic-ICC processors to produce respective dynamic audio routing matrix outputs; and

a plurality of loudspeaker In-Car Communication (Ls-ICC) processors operable to receive and process a respective dynamic audio routing matrix output and to provide an audio signal to corresponding ones of the plurality of loudspeakers distributed within the vehicle.

27. The system of claim 26 where the dynamic audio routing matrix comprises:

a controller coupled to the plurality of Mic-ICC processors;

a mixer coupled to the plurality of Mic-ICC processors; and

a distributor coupled to the plurality of Ls-ICC processors.