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

Abstract

The present disclosure relates to apparatus and methods for active noise cancellation in a personal listening device. A personal listening device (PLD) includes an earphone housing having (a) an inertial sensor for detecting motion of the PLD and generating a motion signal, (b) a pressure sensor for detecting compression of a portion of the PLD and generating a pressure sensor signal, and (c) a speaker for receiving an anti-noise signal and a desired audio signal from an electronic device; and an active noise control (ANC) system that generates the anti-noise signal as one of a first anti-noise signal or a second anti-noise signal. The ANC system includes a processor, a vibration detector that detects vibration of the PLD based on at least one of the motion signal or the pressure sensor signal, and an ANC anti-noise generator that generates a first anti-noise signal when no vibration is detected and generates a second anti-noise signal when vibration is detected. The second anti-noise signal is based on the detected vibration. The processor reconfigures the ANC system for the ANC anti-noise generator to generate the second anti-noise signal.

Description

[0001] This application is a divisional application of a PCT application entering the Chinese national phase, whose international filing date is February 19, 2016, national application number is 201680012033.5, and invention name is “Device and method for active noise cancellation in personal listening devices”. Technical Field

[0002] Embodiments of the present invention generally relate to apparatus and methods for improving active noise control (ANC) in a personal listening device (PLD) by reducing artifacts generated by an ANC system in a noise cancellation control signal when vibration of the personal listening device is detected. More specifically, one embodiment of the present invention relates to a personal listening device having an active noise control (ANC) system that detects vibration of the personal listening device and reduces artifacts generated by the ANC system by reconfiguring the ANC system to generate an anti-noise signal based on the detected vibration. Background Art

[0003] Currently, some personal listening devices such as earbuds, headphones, and headsets include active noise control (ANC) (also known as acoustic noise cancellation) systems that improve the listening experience for the user by eliminating external or background (ambient) noise from being heard by the user. ANC technology cancels external or background sounds by generating a control signal that causes the personal listening device to introduce anti-noise, which is an additional electronically controlled sound field designed to cancel or destructively interfere with the desired external or background sound.

[0004] In some ANC systems, a reference microphone included in a personal listening device (PLD) can be used to pick up the main noise source and generate a reference signal. In some ANC systems, an error microphone also coupled to the personal listening device (PLD) can be used to detect the undesirable noise heard by the user and generate an error signal representing the residual noise that may remain despite the operation of the ANC system. The error signal monitors the performance of the ANC system. The reference signal and the error signal can then be used to control the adaptation of the filters in the ANC system.

[0005] However, personal listening devices that perform ANC often have problems performing ANC in a stable manner. For example, when using a personal listening device while walking, running, or riding a slightly uneven bus, the sound field captured by the reference microphone and the error microphone may be significantly different from the undesirable background noise to be eliminated. As a result, the adaptive filter converges to an incorrect solution, and the anti-noise generated according to this incorrect solution may include audible artifacts that may be significant enough to make the user feel uncomfortable or even nauseous. Summary of the invention

[0006] In general, the present invention relates to personal listening devices such as headphones (e.g., earphones, earbuds) as part of an active noise control (ANC) system for generating an acoustic anti-noise signal that drives a speaker in the earphone. In particular, one embodiment of the present invention relates to improving the ANC of a personal listening device by detecting vibrations of the personal listening device using signals from an accelerometer and / or from a pressure sensor included in the personal listening device (e.g., within an earphone housing) and adapting the ANC system to generate an anti-noise signal based on the detected vibrations.

[0007] In one embodiment of the present invention, a personal listening device (PLD) includes an earphone / headphone housing having a speaker, an error microphone, an inertial sensor, and a pressure sensor therein. The PLD also includes an active noise control (ANC) system. The inertial sensor can detect the movement of the PLD and generate a movement signal. The pressure sensor can detect the compression of a portion of the PLD and generate a pressure sensor signal. The speaker can receive an anti-noise signal and a desired audio signal from an electronic device. The ANC system can generate one of a first anti-noise signal or a second anti-noise signal to drive the speaker and thereby reduce background sounds that may be heard by a user of the PLD. The ANC system may include a processor, a vibration detector for detecting vibration of the PLD based on at least one of the motion signal or the pressure sensor signal, and an ANC adaptive anti-noise generator. The ANC adaptive anti-noise generator can generate a first anti-noise signal when no vibration is detected. The ANC system can generate a second anti-noise signal based on the detected vibration when vibration is detected. In one embodiment, the processor reconfigures the ANC system for the ANC anti-noise generator to generate the second anti-noise.

[0008] In another embodiment of the present invention, a method for active noise cancellation in a PLD begins with an active noise control (ANC) system receiving a reference microphone acoustic signal and an error microphone acoustic signal from the PLD. The ANC system then receives at least one of a motion signal or a pressure sensor signal from the PLD. 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. The ANC system then determines whether a vibration of the PLD is detected based on at least one of the motion signal or the pressure sensor signal. When no vibration is detected, the ANC system generates a first anti-noise signal based on the reference microphone acoustic signal and the error microphone acoustic signal, and when vibration is detected, the ANC system generates a second anti-noise signal. The second anti-noise signal may be based on the detected vibration. The ANC system generating the second anti-noise signal includes reconfiguring the ANC system.

[0009] In another embodiment, a computer-readable storage medium has instructions stored therein, which when executed by a processor causes an active noise control (ANC) system to perform an active noise cancellation method in a PLD. The method begins with the ANC system receiving a reference microphone acoustic signal and an error microphone acoustic signal from the PLD. The ANC system then receives at least one of a motion signal or a pressure sensor signal from the PLD. 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. The ANC system then determines whether a vibration of the PLD is detected based on at least one of the motion signal or the pressure sensor signal. When no vibration is detected, the ANC system generates a first anti-noise signal based on the reference microphone acoustic signal and the error microphone acoustic signal. When vibration is detected, the ANC system generates a second anti-noise signal, wherein the processor reconfigures the ANC system to generate the second anti-noise signal.

[0010] The above summary does not include an exhaustive list of all aspects of the present invention. It is contemplated that the present invention includes all systems, devices and methods that can be implemented by all suitable combinations of the various aspects summarized above and disclosed in the detailed description below and those aspects specifically pointed out in the claims filed with this patent application. Such combinations may have specific advantages not specifically set forth in the above summary of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Embodiments of the present invention are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings, in which like reference numerals indicate like elements. It should be noted that reference to "one" or "an" embodiment in the present disclosure is not necessarily the same embodiment, and this means at least one. In the drawings:

[0012] Figure 1 An example of a personal listening device that may be coupled to a consumer electronics device according to one embodiment of the present invention is shown.

[0013] Figure 2 An illustrative system for active noise cancellation in a personal listening device according to an embodiment of the present invention is shown.

[0014] Figure 3 A block diagram showing details of an illustrative system for active noise cancellation in a personal listening device according to an embodiment of the present invention.

[0015] Figure 4 A flow chart is shown of an exemplary method for active noise cancellation in a personal listening device according to an embodiment of the present invention.

[0016] Figure 5is a block diagram of illustrative components of an electronic device for use with a personal listening device according to aspects of the present disclosure. DETAILED DESCRIPTION

[0017] In the following description, many specific details are given. However, it should be understood that embodiments of the present invention can be practiced without these specific details. In other cases, well-known circuits, structures and techniques are not shown to avoid blurring the understanding of this description.

[0018] Figure 1 An example of a personal listening device (PLD) 200 that can be coupled to a consumer electronic device according to one embodiment of the present invention is shown. The personal listening device can be, for example, a headphone, earphones, or a pair of earbuds. The personal listening device 200 can also be a closed (or sealed) headphone, earphone, or earbud pair, such that the speaker opening of the personal listening device 200 is "sealed" by the contact of the ear to the housing of the device 200 at the area surrounding the speaker opening. The personal listening device 200 can also be a loose fitting earbud.

[0019] like Figure 1 As shown, the personal listening device 200 may be a headset 200 (left) including a pair of earmuffs placed on the user's ears or may be a pair of earplugs 200 (right) placed in the user's ears. Embodiments of the present invention may also use other types of personal listening devices 200. The personal listening device 200 may be coupled to the electronic device 10, and the electronic device 10 transmits an audio signal to the personal listening device 200. The electronic device 10 may be a mobile or fixed personal consumer electronic device. The personal listening device 200 may be coupled to the electronic device 10 via a line 120, such as Figure 1 As shown, or may be coupled to electronic device 10 via a wireless connection (not shown). Figure 1 The personal listening device 200 in the embodiment is a dual-earphone headset. It should be understood that a single earphone or a single-ear headset may also be used. When the user uses the personal listening device to listen to the audio signal from the electronic device 10, environmental noise may also exist (e.g. Figure 1 noise sources in the

[0020] Figure 2 An illustrative system for active noise cancellation in a personal listening device according to an embodiment of the present invention is shown. Figure 2 The system in FIG. 1 shows an electronic device 10 for use with a right side example of a personal listening device 200 according to an embodiment of the present invention. It should be understood that a similar configuration may be included in the left side of the personal listening device 200. Figure 2 Also included is an active noise control (ANC) system 300 that generates an anti-noise signal output by the speaker 240. Figure 2Although illustrated as being separate, according to one embodiment, the ANC system 300 may be included in the housing 210 of the personal listening device 200. In another embodiment, the ANC system 300 may be included in the electronic device 10.

[0021] See also Figure 2 , the personal listening device 200 includes a housing 210, in which at least one reference microphone 220, an error microphone 230, a speaker 240, an inertial sensor 250, and a pressure sensor 260 are installed. The housing 210 can be an earphone housing. The reference microphone 220 and the error microphone 230 can be air interface sound pickup devices that convert sound into electrical signals. In one embodiment, the reference microphone 220 is located inside the housing 210. The reference microphone 220 can be located behind the speaker 240, as shown in the figure, to pick up the main noise (e.g., external noise, background noise, environmental noise, voice, etc.) that is outside the personal listening device 200 and may be heard by the user of the personal listening device 200. In some embodiments, the reference microphone 220 is mounted on the outside of the housing 210, so that the reference microphone 220 is mounted on the outside of the personal listening device 200 to pick up the main noise. In one embodiment, the reference microphone 220 is mounted on the bridge or headband portion of the headset. As Figure 2 As shown, the reference microphone 220 may face the opposite direction of the eardrum. In an embodiment where a plurality of reference microphones 220 are included in the personal listening device 200, the plurality of reference microphones 220 may form one or more microphone arrays that may be used to generate a microphone array beam (i.e., a beamformer), which may be steered to a given direction by emphasizing and de-emphasizing selected microphones 220. In one embodiment, the beamformer may be steered toward the main noise source. Similarly, the microphone array may also exhibit or provide nulls in other given directions. Therefore, the beamforming process (also referred to as spatial filtering) may be a signal processing technique for using a microphone array for directional sound reception. The reference microphone 220 generates and transmits a reference signal to the ANC system 300.

[0022] like Figure 2 As shown, the speaker 240 receives a desired audio signal (e.g., desired audio content) from the electronic device 10 and generates a desired audio signal for the user of the personal listening device 200. The speaker 240 also receives an anti-noise signal from the ANC system 300. The speaker 240 outputs the anti-noise signal, which is a signal that cancels the ambient noise from the audio signal heard by the user of the personal listening device 200.

[0023] like Figure 2As shown, the error microphone 230 is located in front of the speaker 240 and closest to the user's ear canal. The error microphone faces away from the user's eardrum. Therefore, the error microphone 230 receives the acoustic signal output by the speaker 240 heard by the user of the personal listening device 200. The acoustic signal output by the speaker 240 may include undesirable noise that is not eliminated by the ANC system 300. The error microphone 230 thus monitors the performance of the ANC system 300 by detecting the undesirable noise and generating and transmitting an error signal to the ANC system 300. The undesirable noise may be due to the frequency response of the overall sound-generating system, which includes the electroacoustic response of the personal listening device 200 and the physical or acoustic characteristics of the user's ear up to the eardrum that may vary significantly during normal end-user operation and between different users. Using the error signal from the error microphone 230, the ANC system 300 can implement an adaptive filtering scheme (e.g., a filtered-X least squares algorithm (FXLMS)).

[0024] The inertial sensor 250 included in the personal listening device 200 may be a sensing device that measures the inherent acceleration in three directions X, Y, and Z or only one or two directions. For example, the inertial sensor 250 may be an accelerometer, a gyroscope, or a micro-electromechanical system (MEMS). In other embodiments, a force sensor or a position, orientation, and movement sensor may be used instead of the inertial sensor 250. In one embodiment, the inertial sensor 250 detects the motion of the PLD and generates a motion signal, which is transmitted to the ANC system 300. For example, when the user of the personal listening device 200 walks, runs, jumps, or is on an uneven or bumpy ride in a vehicle, the inertial sensor 250 may detect the vibration of the personal listening device 200.

[0025] The pressure sensor 260 included in the personal listening device 200 may be a sensing device that measures compression of a portion of the personal listening device 200 and generates a pressure sensor signal. The pressure sensor 260 may be an optical pressure sensor, a capacitive pressure sensor, a piezoelectric pressure sensor, an electromagnetic pressure sensor, etc. In one embodiment, the ear pad portion of the personal listening device 200 may be made of a soft material (e.g., soft leather, half leather, special polyurethane, etc.). When the user of the personal listening device 200 walks, runs, or is in an uneven or bumpy ride in a vehicle, the ear pad portion of the personal listening device 200 may be compressed and decompressed relative to the user's ear according to the vibration of the personal listening device 200. The pressure sensor 260 may detect, for example, compression (and decompression) of the ear pad portion and generate a pressure sensor signal, which is transmitted to the ANC system 300. In one embodiment, the pressure sensor signal may be used to determine whether the personal listening device is vibrating.

[0026] like Figure 2As shown, the ANC system 300 includes a processor 320, a memory device 330, a vibration detector 310, and an ANC adaptive anti-noise generator 340. The memory device 330, the vibration detector 310, and the ANC adaptive anti-noise generator 340 may be coupled to the processor 320. The memory device 330 may include one or more different types of storage devices such as hard disk drive storage, non-volatile memory, and volatile memory such as dynamic random access memory. The processor 320 may be a microprocessor, a microcontroller, a digital signal processor, or a central processing unit. The term "processor" may refer to a device having two or more processing units or elements, such as a CPU having multiple processing cores. The processor 320 may be used to control the operation of the ANC system 300 by executing software instructions or codes stored in the memory device 330. For example, the processor 320 may execute software instructions or codes stored in the memory device 330, which causes the processor 320 to perform a method for active noise cancellation in a personal listening device 200 according to an embodiment of the present invention. The ANC system 300 operates while the user is, for example, listening to a digital music file stored in the electronic device 10 .

[0027] like Figure 2 As shown, the vibration detector 310 may detect vibration of the personal listening device 200 based on at least one of the motion signal from the inertial sensor 250 or the pressure sensor signal from the pressure sensor 260. The processor 320 may control the vibration detector 310 by executing software instructions or codes stored in the memory device 330 to determine whether vibration of the personal listening device 200 is detected based on the received motion signal from the inertial sensor 250 and the pressure sensor signal from the pressure sensor 260. In one embodiment, the ANC anti-noise generator 340 generates a first anti-noise signal when the vibration detector 310 does not detect vibration, and generates a second anti-noise signal when the vibration detector 310 detects vibration. The second anti-noise signal may be based on the detected vibration. In one embodiment, the processor 320 reconfigures the ANC system 300 for the ANC anti-noise generator 340 to generate the second anti-noise signal.

[0028] like Figure 2 As shown, the ANC adaptive anti-noise generator 340 receives a reference signal from the reference microphone 220 and a desired audio signal from the electronic device 10. The reference signal may be digitized and processed by the ANC adaptive anti-noise generator 340 to generate an anti-noise signal for transmission to the speaker 240 within the personal listening device 200. Figure 3 1 is a block diagram showing details of an ANC adaptive anti-noise generator 340 according to one embodiment of the present invention. The ANC adaptive anti-noise generator 340 may include at least one adaptive filter 350 and an adaptive controller 360. Figure 3 As shown, the at least one adaptive filter 350 receives the reference signal and generates an anti-noise signal that is electronically designed to have the correct pressure amplitude and phase to destructively interfere with the undesired background noise captured by the reference microphone 220. The speaker 240 then outputs the anti-noise signal.

[0029] The ANC adaptive anti-noise generator 340 also receives an error signal from the error microphone 230, which monitors the performance of the ANC system 300 as described above. The error signal may be digitized and processed by the ANC adaptive anti-noise generator 340. In a specific implementation of the adaptive ANC system 300 based on the FXLMS algorithm, identification of the secondary path is required. Therefore, there are two adaptive filters operating simultaneously for each channel: a control filter and a secondary path filter. Identification of the secondary path and / or modeling of the transfer function may be performed online using the downlink (playback) signal as a training signal for the LMS algorithm.

[0030] Implementations of the adaptive ANC system 300 based on the FXLMS algorithm also use a vibration detector 310 to detect when the personal listening device 200 is vibrating. When the personal listening device 200 is vibrating due to a user walking, running, jumping, etc., the reference signal from the reference microphone 220 and the error signal from the error microphone 230 may not be accurate because the signals may include vibration and / or compression of the personal listening device 200 as part of the noise to be eliminated by the ANC system 300. Therefore, while the personal listening device 200 may act as an interfering signal to the adaptive filtering algorithm, the signals from the reference microphone 220 and from the error microphone 230 may cause the filtering to diverge. Therefore, the vibration detector 310 is used to determine when the personal listening device 200 is vibrating. When vibration of the personal listening device 200 is detected, the processor 320 may prevent the corrupted reference signal and the corrupted error signal from being used to adapt the filter 350 in the ANC adaptive anti-noise generator 340 of the ANC system 300. Thus, the at least one adaptive filter 350 is prevented from diverging or becoming unstable. In one embodiment, the ANC adaptive anti-noise generator 340 generates an anti-noise signal based on the reference signal and the error signal when no vibration is detected. However, when the personal listening device 200 vibrates, the anti-noise signal based on the reference signal and the error signal causes the personal listening device 200 to generate anti-noise including artifacts. Therefore, when the vibration detector 310 detects vibration, the ANC adaptive anti-noise generator 340 generates a second anti-noise signal based on the detected vibration.

[0031] In one embodiment, the vibration detector 310 receives at least one of a motion signal from the inertial sensor 250 or a pressure sensor signal from the pressure sensor 260. The motion signal and the pressure sensor signal may be digitized and processed by the vibration detector 310 to determine whether the personal listening device 200 is vibrating. In one embodiment, the memory device 330 stores a plurality of predetermined sensor data patterns, including patterns indicating the following contexts: walking, jumping, running, and vehicle motion or vibration. In this embodiment, when the vibration detector 310 matches at least one of the motion signal or the pressure sensor signal with at least one of the predetermined sensor data patterns, the vibration detector 310 determines that vibration of the personal listening device 200 is detected.

[0032] In one embodiment, when the vibration detector 310 detects vibration, the processor 320 reconfigures the ANC system 300 for the ANC anti-noise generator 340 to generate a second anti-noise signal based on the detected vibration. The processor 320 in the ANC system 300 may implement a feed-forward, feedback, or hybrid noise control algorithm. Upon detecting vibration of the personal listening device 200, the processor 320 may reconfigure the ANC system 300 by, for example, adapting coefficients of a finite impulse response (FIR) filter (e.g., a secondary path) using an LMS adaptive algorithm, adapting coefficients of the FIR filter (e.g., a control filter path) according to a filtered-X LMS algorithm, and reconfiguring the ANC system 300 to change the adaptation of the FIR filter. For example, when vibration is detected, the processor 320 may lock filter coefficients of an adaptive filter 350 included in the ANC system 300, or the processor may alternatively lock filtering of the adaptive filter 350. Locking filter coefficients or locking filtering may also be referred to as "freezing" an adaptive filter. Thus, the adaptive filter 350 remains in a previous acceptable state (e.g., not diverging or unstable) and generates an anti-noise signal. In another embodiment, to reconfigure the ANC system 300, the processor 320 changes the speed of updates to the adaptive filter 350 by the adaptive filter controller 360 included in the ANC system 300. For example, if the vibration detector 310 matches the motion signal or the pressure signal with a predetermined sensor data pattern associated with a walking context, the processor 320 may increase the speed of adaptive filter updates between steps and may slow down the speed of adaptive filter updates when the user steps (e.g., when the user's foot hits the ground). Thus, the ANC system 300 takes into account that changes in the pressure level in the ear cup due to the user's steps affect the reference microphone signal from the reference microphone 220. In another embodiment, to reconfigure the ANC system 300 when vibration is detected, the processor 320 selects predetermined adaptive filter coefficients associated with the at least one of the predetermined sensor data patterns. For example, if the vibration detector 310 matches the motion signal or the pressure signal with a predetermined sensor data pattern associated with a walking context, the processor 320 may select predetermined adaptive filter coefficients associated with the walking context. The predetermined adaptive filter coefficients associated with each of the contexts may be stored in the memory device 330. In this embodiment, the processor 320 overwrites the filter coefficients of the adaptive filter 350 calculated by the adaptive filter controller 360 included in the ANC system 300 with the selected predetermined filter coefficients. In another embodiment, in order to reconfigure the ANC system 300 when vibration is detected, the processor 320 applies a jacket to the filter coefficients of the adaptive filter 350 included in the ANC system 300. The jacket establishes the maximum and minimum values ​​of the desired filter coefficients.Thus, when vibration of the personal listening device 200 causes the adaptive filter controller 360 to generate erroneous coefficients for the adaptive filter 350 in the ANC system 300, the processor 320 applies the jacket to the erroneous coefficients, which causes the erroneous coefficients that exceed the maximum value established by the jacket or fall below the minimum value established by the jacket to be corrected by the processor 320. The corrected coefficient values ​​are values ​​that are within the established limits of the jacket. In one embodiment, when vibration is detected, the processor 320 may mute the anti-noise signal output from the speaker 240. However, it should be noted that muting the anti-noise signal when vibration is detected in the personal listening device 200 may introduce artifacts in the acoustic signal heard by the user.

[0033] In addition, the following embodiments of the present invention can be described as a process, which is usually depicted as a flow chart, a flow chart, a structure diagram or a block diagram. Although the flow chart can describe the operation as a sequential process, multiple operations in these operations can be performed in parallel or simultaneously. In addition, the order of the operations can be rearranged. The process terminates when its operation is completed. The process can correspond to a method, a process, etc.

[0034] Figure 4 A flow chart is shown of an exemplary method for improving active noise cancellation in a personal listening device according to an embodiment of the present invention. Figure 4 The method 400 in FIG. 4 begins when, at block 401, the ANC system 300 receives a reference microphone acoustic signal and an error microphone acoustic signal from a personal listening device 200. At block 402, the ANC system 300 receives at least one of a motion signal or a pressure sensor signal from the personal listening device 200. The motion signal is based on the detected motion of the personal listening device, and the pressure sensor signal is based on the detected compression of a portion of the personal listening device 200. At block 403, the ANC system 300 determines whether a vibration of the personal listening device is detected based on at least one of the motion signal or the pressure sensor signal. If, at block 403, the ANC system 300 determines that no vibration is detected, the method 400 proceeds to block 404, and the ANC system generates a first anti-noise signal based on the reference microphone acoustic signal and the error microphone acoustic signal. If, at block 403, the ANC system 300 determines that vibration is detected, the method 400 proceeds to block 405, and the ANC system 300 generates a second anti-noise signal. The second anti-noise signal may be based on the detected vibration. In one embodiment, at block 405 , the ANC system 300 is reconfigured by the processor 320 to generate a second anti-noise signal.

[0035] The following references Figure 5 A general description of suitable electronic devices for performing these functions is provided. In particular, Figure 5is a block diagram illustrating various components that may be present in an electronic device suitable for use with the present technology. An example of a suitable electronic device includes a computer, a handheld portable electronic device, a tablet electronic device, and the like. These types of electronic devices, as well as other electronic devices that provide similar voice communication capabilities (e.g., VoIP, telephony, and the like), may be used in conjunction with the present technology.

[0036] Keep the above points in mind. Figure 5 1 is a block diagram illustrating components that may be present in one such electronic device 10 that enable the device 10 to operate in accordance with the techniques discussed herein. Figure 5 The various functional blocks shown may include hardware elements (including circuits), software elements (including computer code stored on a computer-readable medium such as a hard drive or system memory), or a combination of both hardware and software elements. Figure 5 This is merely one example of one particular implementation and is intended merely to illustrate the types of components that may be present in the electronic device 10. For example, in the illustrated embodiment, these components may include a display 12, input / output (I / O) ports 14, input structures 16, one or more processors 18, a memory device 20, a non-volatile storage device 22, an expansion card 24, RF circuitry 26, and a power supply 28.

[0037] The above-described embodiment of the present invention is a personal listening device (PLD) with an active noise control (ANC) system, including: means for receiving a reference microphone acoustic signal and an error microphone acoustic signal from the PLD; means for 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; means for determining whether vibration of the PLD is detected based on at least one of the motion signal or the pressure sensor signal; means for generating a first anti-noise signal based on the reference microphone acoustic signal and the error microphone acoustic signal when no vibration is detected; and means for generating a second anti-noise signal when vibration is detected, wherein the processor reconfigures the ANC system to generate the second anti-noise signal. The ANC system may or may not be included in an electronic device coupled to the PLD, in which the electronic device transmits an audio signal to the PLD.

[0038] Although the present invention has been described with reference to several embodiments, it will be appreciated by those skilled in the art that the present invention is not limited to the embodiments described, but may be practiced with modifications and changes within the spirit and scope of the appended claims. Therefore, the description is to be regarded as illustrative rather than restrictive. There are a number of other variations of the various aspects of the present invention described above, which are not presented in detail for the sake of brevity. Therefore, other embodiments are within the scope of the claims.

Claims

1. A personal listening device PLD, comprising: an earphone housing having a sensor and a speaker therein, the speaker for receiving an anti-noise signal and a desired audio signal, wherein the sensor is for generating a sensor signal that captures vibrations of the PLD; and An active noise control (ANC) system, the active noise control system is used to generate the anti-noise signal as one of the first anti-noise signal or the second anti-noise signal, the ANC system comprising: processor, a memory device for storing a plurality of predetermined sensor data patterns, including patterns indicative of walking, jumping, running, vehicle motion, or vehicle vibration, a vibration detector coupled to the processor and to the memory device, the vibration detector for detecting vibration of the PLD based on the sensor signal from the sensor matching at least one of the plurality of predetermined sensor data patterns, and an ANC anti-noise generator coupled to the processor, wherein the processor configures the ANC anti-noise generator to generate the first anti-noise signal when the vibration detector detects no vibration, and reconfigures the ANC anti-noise generator to generate the second anti-noise signal when the vibration detector detects vibration of the PLD based on the sensor signal matching at least one of the plurality of predetermined sensor data patterns.

2. The PLD of claim 1, wherein the sensor comprises at least one of an accelerometer, a gyroscope, or a micro-electro-mechanical system (MEMS).

3. The PLD of 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 of claim 1 , wherein the processor reconfigures the ANC system comprises: The processor locks a filter coefficient of an adaptive filter included in the ANC system or locks filtering performed by the adaptive filter included in the ANC system.

5. The PLD of claim 1 , wherein the processor reconfigures the ANC system comprises: The processor varies a rate of updates to an adaptive filter performed by an adaptive filter controller included in the ANC system.

6. The PLD of claim 1 , wherein the processor reconfigures 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 adaptive filter coefficients are stored in the memory device, and The processor overwrites filter coefficients of an adaptive filter calculated by an adaptive filter controller included in the ANC system with the predetermined adaptive filter coefficients.

7. The PLD of claim 1 , wherein the processor reconfigures the ANC system comprises: The processor applies jacketing to filter coefficients of an adaptive filter included in the ANC system.

8. The PLD of claim 1 , wherein the processor reconfiguring the ANC system comprises: The processor mutes the anti-noise signal to the speaker.

9. A method for active noise cancellation in a personal listening device (PLD), the method comprising: An active noise control (ANC) system receives a reference microphone acoustic signal and an error microphone acoustic signal from the PLD; The ANC system receives a sensor signal from the PLD, wherein the sensor signal is responsive to vibration of the PLD; the ANC system determining whether vibration of the PLD is detected based on the sensor signal matching at least one of a plurality of predetermined sensor data patterns stored in a memory of the PLD, wherein the plurality of predetermined sensor data patterns include patterns indicative of background of pedestrian and vehicular motion; When no vibration is detected, the ANC system generates a first anti-noise signal based on the reference microphone acoustic signal and the error microphone acoustic signal; and The ANC system generates a second anti-noise signal when vibration is detected based on the sensor signal matching at least one of the plurality of predetermined sensor data patterns stored in the memory of the PLD, wherein the ANC system generating the second anti-noise signal includes reconfiguring the ANC system.

10. The method of claim 9, wherein reconfiguring the ANC system comprises: Filter coefficients of an adaptive filter included in the ANC system are locked.

11. The method of claim 9, wherein reconfiguring the ANC system comprises: A speed of updating of an adaptive filter by an adaptive filter controller included in the ANC system is varied.

12. The method of claim 9, wherein reconfiguring the ANC system comprises: selecting predetermined adaptive filter coefficients associated with said at least one of said predetermined sensor data patterns, wherein said predetermined adaptive filter coefficients are stored in said memory device, and The filter coefficients of an adaptive filter calculated by an adaptive filter controller included in the ANC system are overwritten with the predetermined adaptive filter coefficients.

13. The method of claim 9, wherein reconfiguring the ANC system comprises: Jacketing is applied to filter coefficients of an adaptive filter included in the ANC system.

14. A computer readable storage medium having stored therein instructions, which when executed by a processor cause 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 a sensor signal from the PLD, wherein the sensor signal captures vibrations of the PLD; determining whether vibration of the PLD is detected based on the sensor signal matching at least one of a plurality of predetermined sensor data patterns stored in a memory of the PLD, wherein the plurality of predetermined sensor data patterns include patterns indicative of backgrounds of pedestrian and vehicular motion; generating a first anti-noise signal based on the reference microphone acoustic signal and the error microphone acoustic signal when no vibration is detected; as well as A second anti-noise signal is generated when vibration is detected based on the sensor signal matching at least one of the plurality of predetermined sensor data patterns stored in the memory of the PLD, wherein the processor reconfigures the ANC system to generate the second anti-noise signal.

15. The computer-readable storage medium of claim 14, wherein the ANC system is included in an electronic device coupled to the PLD, the electronic device transmitting audio signals to the PLD.

16. The computer-readable storage medium of claim 14, wherein the ANC system is included in the PLD.

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