Adaptive personal active noise system

• US 20060251266A1
• Filed: 04/13/2006
• Published: 11/09/2006
• Est. Priority Date: 05/06/1997
• Status: Abandoned Application

• Current Assignee: Adaptive Technologies, Inc.
• Original Assignee: Adaptive Technologies, Inc.
• Inventors: Saunders, William R., Vaudrey, Michael A.
• Application Number:
  US11/403,573
• Publication Number:
  US 20060251266A1
• Time in Patent Office: Days
• US Class Current: 381/71.100
• CPC Class Codes: G10K 11/17854 the filter being an adaptive filter
• CPC Class Codes: G10K 11/17857 Geometric disposition, e.g. placement of microphones
• CPC Class Codes: G10K 11/17881 the reference signal being an acoustic signal, e.g. recorded with a microphone
• CPC Class Codes: G10K 2210/10 Applications
• CPC Class Codes: G10K 2210/101 One dimensional
• CPC Class Codes: G10K 2210/108 Communication systems, e.g. where useful sound is kept and noise is cancelled
• CPC Class Codes: G10K 2210/1081 Earphones, e.g. for telephones, ear protectors or headsets
• CPC Class Codes: G10K 2210/1082 Microphones, e.g. systems using "virtual" microphones
• CPC Class Codes: G10K 2210/128 Vehicles
• CPC Class Codes: G10K 2210/1282 Automobiles
• CPC Class Codes: G10K 2210/3016 Control strategies, e.g. energy minimization or intensity measurements
• CPC Class Codes: G10K 2210/3025 Determination of spectrum characteristics, e.g. FFT
• CPC Class Codes: G10K 2210/3026 Feedback
• CPC Class Codes: G10K 2210/3027 Feedforward
• CPC Class Codes: G10K 2210/3031 Hardware, e.g. architecture
• CPC Class Codes: G10K 2210/3033 Information contained in memory, e.g. stored signals or transfer functions
• CPC Class Codes: G10K 2210/30351 Identification of the environment for applying appropriate model characteristics
• CPC Class Codes: G10K 2210/3042 Parallel processing
• CPC Class Codes: G10K 2210/3046 Multiple acoustic inputs, multiple acoustic outputs
• CPC Class Codes: G10K 2210/3056 Variable gain
• CPC Class Codes: G10K 2210/3214 : Architectures, e.g. special constructional features or arrangements of features
• CPC Class Codes: G10K 2210/3217 : Collocated sensor and cancelling actuator, e.g. "virtual earth" designs
• CPC Class Codes: G10K 2210/3219 : Geometry of the configuration
• CPC Class Codes: G10K 2210/3221 : Headrests, seats or the like, for personal ANC systems
• CPC Class Codes: G10K 2210/3222 : Manual tuning
• CPC Class Codes: G10K 2210/506 : Feedback, e.g. howling
• CPC Class Codes: G10K 2210/511 : Narrow band, e.g. implementations for single frequency cancellation
• CPC Class Codes: H04R 1/1083 : Reduction of ambient noise active noise reduction per se G10K11/175; protective devices for the ear, e.g. providing acoustic protection A61F11/06

Abstract

An improved active noise reduction system which has a transducer, an electro-acoustic sensing means including adjacent to the transducer, an attenuation means with electro-acoustic sensing means to attenuate selected sound frequencies, said system utilizing both feed forward control means and feedback control means comprising a heteronomous electronic controller with algorithmic transfer function and said controller being individually operable.

Claims

1. A heteronomous controller of a personal active noise attenuation system comprising:

a feedback controller adapted for receiving an acoustically transduced signal from a noise error sensor and for generating a feedback active noise attenuating control signal portion;

a feedforward controller adapted for;

receiving the acoustically transduced signal from the noise error sensor;

receiving a noise reference signal from a noise reference signal sensor; and

applying an adaptive signal processing algorithm to the acoustically transduced signal from the noise error sensor and to the noise reference signal to generate an adaptive active noise attenuation control signal portion; and

a linear combiner adapted for summing a linear combination of the feedback active noise attenuating control signal portion and the adaptive active noise attenuation control signal portion so as to generate a heteronomous control signal.

2. The heteronomous controller of claim 1 further comprising a compensator adapted for canceling a feedback path from the noise reference signal sensor before application of the adaptive signal processing algorithm, wherein the feed forward controller receives the noise reference signal from the noise reference signal sensor via the compensator

3. The heteronomous controller of claim 2, wherein the feedback compensator is an analog filter.

4. The heteronomous controller of claim 2, wherein the compensator is a digital filter.

5. The heteronomous controller of claim 1, wherein the adaptive signal processing algorithm is an adaptive feedforward algorithm.

6. The heteronomous controller of claim 1, wherein the adaptive signal processing algorithm is an adaptive feedback algorithm.

7. The compensator of claim 2, wherein the compensator is executed on the feedforward controller that executes the adaptive signal processing algorithm.

8. The compensator of claim 2, wherein the feedforward controller is further adapted for minimizing a sensitivity of a loop transfer function between the acoustically transduced signal from the noise error sensor and the adaptive active noise attenuating control signal portion of the heteronomous control signal.

9. The heteronomous controller of claim 1, wherein the noise error sensor is a microphone.

10. The heteronomous controller of claim 1, wherein the noise error sensor is an accelerometer.

11. The heteronomous controller of claim 1, wherein the noise error sensor is spatially adaptable in the noise field.

12. The heteronomous controller of claim 1, wherein the noise reference signal sensor is a microphone.

13. The heteronomous controller of claim 1, wherein the noise reference signal sensor is an accelerometer.

14. The heteronomous controller of claim 1, wherein the noise reference signal sensor is the noise error sensor.

15. The heteronomous controller of claim 1, wherein the noise reference signal sensor is spatially adaptable in the noise field.

16. The heteronomous controller of claim 1, wherein the personal active noise attenuation system is a headset system comprising a head-mounting portion, earcups, a noise error sensor, a noise reference signal sensor, and an electroacoustic control speaker system.

17. The heteronomous controller of claim 1, wherein the personal active noise attenuation system is a silent seat comprising a noise error sensor, a reference signal sensor, and an electroacoustic control speaker system.

18. The heteronomous controller of claim 1, wherein the linear combiner is an analog summing amplifier.

19. The heteronomous controller of claim 1, wherein the linear combiner is adapted for proportionally combining the feedback active noise attenuation control signal portion and the adaptive active noise attenuation control signal portion in the feed forward controller.

20. The heteronomous controller of claim 1, where the linear combiner summer is adapted for outputting selectively controlled proportions of the feedback active noise attenuation control signal portion and the adaptive active noise attenuation control signal portion.

21. The heteronomous controller of claim 1, wherein the personal active noise attenuation system is a headset and earplug system comprising a head mounting portion, earcups, and earplugs, further comprising a noise error sensor, a noise reference signal sensor, and an electroacoustic control speaker system.

22. The heteronomous controller of claim 1, wherein the personal active noise attenuation system is an earplug system comprising earplugs, a noise error sensor, a noise reference signal sensor, and an electroacoustic control speaker system.

23. The heteronomous controller and earplug system of claim 22 where earplugs are custom earmolds, foam earplugs, flanged earplugs, acrylic earplugs.

24. The heteronomous controller of claim 23, wherein the electroacoustic control speaker system is comprised of one or more speakers.