Apparatus and method of active noise cancellation in a personal listening device

Patent metadata

Field	Value
Publication number	US-9706288-B2
Application number	US-201514656443-A
Country	US
Kind code	B2
Filing date	Mar 12, 2015
Priority date	Mar 12, 2015
Publication date	Jul 11, 2017
Grant date	Jul 11, 2017

Abstract

Personal listening device (PLD) includes earphone housing having therein (a) inertial sensor to detect motion of PLD and to generate motion signal, (b) pressure sensor to detect compression of portion of PLD and to generate pressure sensor signal, and (c) speaker to receive anti-noise signal and desired audio signal from electronic device, and active noise control (ANC) system to generate anti-noise signal as being one of first or second anti-noise signal. ANC system includes processor, vibration detector to detect vibration of the PLD based on at least one of motion signal or pressure sensor signal, and ANC anti-noise generator to generate first anti-noise signal when vibrations are not detected by vibration detector, and to generate second anti-noise signal when vibrations are detected by vibration detector. Second anti-noise signal is based on detected vibrations. Processor reconfigures ANC system for ANC anti-noise generator to generate second anti-noise signal. Other embodiments are described.

First claim

The invention claimed is:

1. A personal listening device (PLD) comprising:
an earphone housing having therein (a) an inertial sensor to detect motion of the PLD and to generate a motion signal, (b) a pressure sensor to detect compression of a portion of the PLD and to generate pressure sensor signal, and (c) a speaker to receive an anti-noise signal and a desired audio signal from an electronic device; and
an active noise control (ANC) system to generate the anti-noise signal as being one of a first anti-noise signal or a second anti-noise signal, the ANC system includes
a processor,
a vibration detector coupled to the processor, the vibration detector to detect a vibration of the PLD based on at least one of the motion signal or the pressure sensor signal, and
an ANC anti-noise generator coupled to the processor, the ANC anti-noise generator to generate the first anti-noise signal when vibrations are not detected by the vibration detector, and to generate the second anti-noise signal when vibrations are detected by the vibration detector, the second anti-noise signal being based on detected vibrations,
wherein the processor reconfigures the ANC system for the ANC anti-noise generator to generate the second anti-noise signal.

2. The PLD in claim 1 , wherein the inertial sensor comprises at least one of an accelerometer, a gyroscope, or a microelectromechanical system (MEMS), wherein the inertial sensor detects motion in at least three axes: x-axis, y-axis, z-axis.

3. The PLD in claim 1 , wherein the first anti-noise signal is based on at least one of a reference microphone signal or an error microphone signal.

4. The PLD in claim 3 , wherein the ANC system comprises a memory device:
to store a plurality of predetermined sensor data patterns including patterns that indicate the contexts of: walking, jumping, running, and vehicle motions or vibrations.

5. The PLD in claim 4 , wherein the vibration detector is coupled to the memory device and wherein the vibration detector to detect the vibration comprises:
the vibration detector matching at least one of the motion signal or the pressure sensor signal with at least one of the predetermined sensor data patterns.

6. The PLD of claim 5 , wherein the processor reconfiguring the ANC system comprises:
the processor locking filter coefficients of an adaptive filter included in the ANC system or locking filtering by the adaptive filter included in the ANC system.

7. The PLD of claim 5 , wherein the processor reconfiguring the ANC system comprises:
the processor changing a speed of updates made to an adaptive filter by an adaptive filter controller included in the ANC system.

8. The PLD of claim 5 , wherein the processor reconfiguring the ANC system comprises:
the processor selecting predetermined adaptive filter coefficients associated with the at least one of the predetermined sensor data patterns, wherein the predetermined coefficients are stored in the memory device, and
the processor overriding filter coefficients of an adaptive filter, that were computed by an adaptive filter controller included in the ANC system, with the predetermined filter coefficients.

9. The PLD of claim 5 , wherein the processor reconfiguring the ANC system comprises:
the processor applying a jacket on filter coefficients of an adaptive filter included in the ANC system.

10. The PLD of claim 5 , wherein the processor reconfiguring the ANC system comprises:
the processor muting the anti-noise signal output from the speaker.

11. A method of active noise cancellation in a personal listening device (PLD) comprising:
receiving by an active noise control (ANC) system a reference microphone acoustic signal and an error microphone acoustic signal from the PLD;
receiving by the ANC system at least one of a motion signal or a pressure sensor signal from the PLD, wherein the motion signal is based on a detected motion of the PLD and the pressure sensor signal is based on a detected compression of a portion of the PLD;
determining by the ANC system whether vibrations of the PLD are detected based on at least one of the motion signal or the pressure sensor signal;
when vibrations are not detected, generating by the ANC system a first anti-noise signal based on the reference microphone acoustic signal and the error microphone acoustic signal; and
when vibrations are detected, generating by the ANC system a second anti-noise signal, wherein generating by the ANC system the second anti-noise signal includes reconfiguring the ANC system.

12. The method of claim 11 , wherein determining by the ANC system whether vibrations of the PLD system are detected comprises:
the ANC system matching at least one of the motion signal or the pressure sensor signal with at least one of a plurality of predetermined sensor data patterns.

13. The method of claim 12 , wherein the plurality of predetermined sensor data patterns are stored in a memory device included in the ANC system.

14. The method of claim 13 , wherein the plurality of predetermined sensor data patterns include patterns that indicate the contexts of walking, jumping, running, and vehicle motions or vibrations.

15. The method of claim 14 , wherein reconfiguring the ANC system comprises:
locking filter coefficients of an adaptive filter included in the ANC system.

16. The method of claim 14 , wherein reconfiguring the ANC system comprises:
changing a speed of updates made to an adaptive filter by an adaptive filter controller included in the ANC system.

17. The method of claim 14 , wherein reconfiguring the ANC system comprises:
selecting predetermined adaptive filter coefficients associated with the at least one of the predetermined sensor data patterns, wherein the predetermined coefficients are stored in the memory device, and
a processor overriding filter coefficients of an adaptive filter, that were computed by an adaptive filter controller included in the ANC system, with the predetermined filter coefficients.

18. The method of claim 14 , wherein reconfiguring the ANC system comprises:
a processor applying a jacket on filter coefficients of an adaptive filter included in the ANC system.

19. A computer-readable non-transitory storage medium having stored therein instructions, when executed by a processor, causes an active noise control (ANC) system to perform a method of active noise cancellation in a personal listening device (PLD), the method comprising: receiving a reference microphone acoustic signal and an error microphone acoustic signal from the PLD; receiving at least one of a motion signal or a pressure sensor signal from the PLD, wherein the motion signal is based on a detected motion of the PLD and the pressure sensor signal is based on a detected compression of a portion of the PLD; determining whether vibrations of the PLD are detected based on at least one of the motion signal or the pressure sensor signal; when vibrations are not detected, generating a first anti-noise signal based on the reference microphone acoustic signal and the error microphone acoustic signal; and when vibrations are detected, generating a second anti-noise signal, wherein the processor reconfigures the ANC system to generate the second anti-noise signal.

20. The computer-readable non-transitory storage medium of claim 19 , wherein the ANC system is included in an electronic device coupled to the PDL, the electronic device transmitting an audio signal to the PDL.

21. The computer-readable non-transitory storage medium of

Assignees

• Apple Inc

Inventors

• Terlizzi Jeffrey

Classifications

• G10K2210/129

  Vibration, e.g. instead of, or in addition to, acoustic noise · CPC title

• H04R1/1083

  Reduction of ambient noise (active noise reduction per se G10K11/175; protective devices for the ear, e.g. providing acoustic protection A61F11/06) · CPC title

• H04R2460/01

  Hearing devices using active noise cancellation · CPC title

• H04R1/1091 Primary

  Details not provided for in groups H04R1/1008 - H04R1/1083 · CPC title

• G10K11/178 Primary

  by electro-acoustically regenerating the original acoustic waves in anti-phase · CPC title