NOISE-CANCELLATION SYSTEMS AND METHODS

• US 20200135162A1
• Filed: 10/31/2018
• Published: 04/30/2020
• Est. Priority Date: 10/31/2018
• Status: Active Grant

• Current Assignee: Bose Corporation
• Original Assignee: Bose Corporation
• Inventors: Hein, Travis, Farahbakhsh, Siamak, Bernstein, Eric
• Granted Patent: US 10,741,163 B2
• Time in Patent Office: Days
• CPC Class Codes: B60W 40/06 Road conditions
• CPC Class Codes: G10K 11/002 Devices for damping, suppressing, obstructing or conducting sound in acoustic devices G10K1/06 - G10K1/10 take precedence; for electro-mechanical transducers for communication H04R3/002
• CPC Class Codes: G10K 11/17825 Error signals
• CPC Class Codes: G10K 11/17833 by using a self-diagnostic function or a malfunction prevention function, e.g. detecting abnormal output levels
• CPC Class Codes: G10K 11/17854 the filter being an adaptive filter
• CPC Class Codes: G10K 11/17881 the reference signal being an acoustic signal, e.g. recorded with a microphone
• CPC Class Codes: G10K 2210/1282 Automobiles
• CPC Class Codes: G10K 2210/12821 Rolling noise; Wind and body noise
• CPC Class Codes: G10K 2210/3016 Control strategies, e.g. energy minimization or intensity measurements
• CPC Class Codes: G10K 2210/3018 Correlators, e.g. convolvers or coherence calculators
• CPC Class Codes: G10K 2210/3026 Feedback
• CPC Class Codes: G10K 2210/3033 Information contained in memory, e.g. stored signals or transfer functions
• CPC Class Codes: G10K 2210/3039 Nonlinear, e.g. clipping, numerical truncation, thresholding or variable input and output gain
• CPC Class Codes: G10K 2210/503 Diagnostics; Stability; Alarms; Failsafe

Abstract

A road noise-cancellation system, comprising: an actuator disposed in a vehicle cabin; a controller comprising a processor and non-volatile memory, the controller being programmed to: generate a noise-cancellation signal with a noise-cancellation filter including a first plurality of coefficients, the noise-cancellation signal being based on the first plurality of coefficients, the noise-cancellation signal being transduced by the actuator to generate a noise-cancellation audio signal based on the noise-cancellation signal, the noise-cancellation audio signal destructively interfering with an undesired noise in a noise-cancellation zone; adjust the first plurality of coefficients of the noise-cancellation filter based on one or more input signals to provide a second plurality of coefficients; store the second plurality of coefficients in the non-volatile memory during a shutdown sequence or at the end of an interval; and restore the second plurality of coefficients from non-volatile memory to the noise-cancellation filter after (i) startup or (ii) determining that a third plurality of coefficients, provided by a second adjustment, are divergent or unstable.

Claims

1. A road noise-cancellation system, comprising:

an actuator disposed in a vehicle cabin;

a controller comprising a processor and non-volatile memory, the controller being programmed to;

generate a noise-cancellation signal with a noise-cancellation filter including a first plurality of coefficients, the noise-cancellation signal being based on the first plurality of coefficients, the noise-cancellation signal being transduced by the actuator to generate a noise-cancellation audio signal based on the noise-cancellation signal, the noise-cancellation audio signal destructively interfering with an undesired noise in a noise-cancellation zone;

adjust the first plurality of coefficients of the noise-cancellation filter based on one or more input signals to provide a second plurality of coefficients;

store the second plurality of coefficients in the non-volatile memory during a shutdown sequence or at the end of an interval; and

restore the second plurality of coefficients from non-volatile memory to the noise-cancellation filter after determining that a third plurality of coefficients, provided by a second adjustment, are divergent or unstable.

2. The road noise-cancellation system of claim 1, wherein the step of restoring the second plurality of coefficients comprises loading the second plurality of coefficients from non-volatile memory into volatile memory.

4. The road noise-cancellation system of claim 1, where in the length of the interval is determined according to the road conditions.

5. The road noise-cancellation system of claim 1, wherein the second plurality of coefficients are only stored when the second plurality of coefficients are determined to be stable.

6. The road noise-cancellation system of claim 1, wherein the shutdown sequence is initiated by a user turning a key and persists for a predetermined period of time thereafter.

7. The road noise-cancellation system of claim 1, wherein the first plurality of coefficients are adjusted according to an adaptive processing module.

8. The road noise-cancellation system of claim 1, wherein the one or more input signals are a noise sensor signal from a noise sensor and an error sensor signal from an error sensor.

9. The road noise-cancellation system of claim 8, wherein the coefficients are adjusted at least in part to minimize the error sensor signal.

10. The road noise-cancellation system of claim 8, wherein the error sensor is a microphone disposed within the vehicle cabin.

3. A road noise-cancellation system, comprising:

an actuator disposed in a vehicle cabin;

a controller comprising a processor and non-volatile memory, the controller being programmed to;

generate a noise-cancellation signal with a noise-cancellation filter including a first plurality of coefficients, the noise-cancellation signal being based on the first plurality of coefficients, the noise-cancellation signal being transduced by the actuator to generate a noise-cancellation audio signal based on the noise-cancellation signal, the noise-cancellation audio signal destructively interfering with an undesired noise in a noise-cancellation zone;

adjust the first plurality of coefficients of the noise-cancellation filter based on one or more input signals to provide a second plurality of coefficients;

store the second plurality of coefficients in the non-volatile memory during a shutdown sequence or at the end of an interval, wherein the interval is periodic; and

restore the second plurality of coefficients from non-volatile memory to the noise-cancellation filter after (i) startup or (ii) determining that a third plurality of coefficients, provided by a second adjustment, are divergent or unstable.

11. A method for persistently storing the last state of a road noise cancellation system, comprising the steps of:

generating a noise-cancellation signal with a noise-cancellation filter including a first plurality of coefficients, the noise-cancellation signal being based on the first plurality of coefficients, the noise-cancellation signal being transduced by an actuator to generate a noise-cancellation audio signal based on the noise-cancellation signal, the noise-cancellation audio signal destructively interfering with an undesired noise in a noise-cancellation zone;

adjusting the first plurality of coefficients of the noise-cancellation filter based on one or more input signals to provide a second plurality of coefficients;

storing the second plurality of coefficients in the non-volatile memory during a shutdown sequence or at the end of an interval; and

restoring the second plurality of coefficients from non-volatile memory to the noise-cancellation filter after determining that a third plurality of coefficients, provided by a second adjustment, are divergent or unstable.

12. The method of claim 11, wherein the step of restoring the second plurality of coefficients comprises loading the second plurality coefficients from non-volatile memory into volatile memory.

14. The method of claim 11, where in the length of the interval is determined according to the road conditions.

15. The method of claim 11, wherein the second plurality of coefficients are only stored when the second plurality of coefficients are determined to be stable.

16. The method of claim 11, wherein the shutdown sequence is initiated by a user turning a key and persists for a predetermined period of time thereafter.

17. The method of claim 11, wherein the first plurality of coefficients are adjusted according to an adaptive processing module.

18. The method of claim 11, wherein the one or more input signals are a noise sensor signal from a noise sensor and an error sensor signal from an error sensor.

19. The method of claim 18, wherein the first plurality of coefficients are adjusted at least in part to minimize the error sensor signal.

20. The method of claim 18, wherein the error sensor is a microphone disposed within a vehicle cabin.

13. (canceled)