An active noise cancellation (ANC) system is provided with at least one loudspeaker to project an anti-noise sound within a room in response to receiving an anti-noise signal. A first controller is programmed to adjust a transfer function indicative of a secondary path between the at least one loudspeaker and at least one microphone within the room based on a resonance frequency of the at least one loudspeaker, and to generate the anti-noise signal based on the adjusted transfer function.

A noise cancelling system for a vehicle includes a microphone, at least one first sensor configured to collect first data related to an element that generates a noise sound, at least one second sensor configured to collect second data related to an element that changes a secondary path of the noise sound, a controller configured to select a secondary path model corresponding to the second data from among a plurality of pre-stored secondary path models, input the first data to a secondary path filter corresponding to the selected secondary path model, and generate an anti-noise signal based on output data of the secondary path filter and error data received from the microphone, and a speaker configured to output an anti-noise sound based on the anti-noise signal.

The present invention relates to methods, apparatus and systems for audio playback via a personal audio device following a biometric process. A personal audio device may be used to obtain ear model data for authenticating a user via an ear biometric authentication system. Owing to that successful authentication, the electronic device is informed of the person who is listening to audio playback from the device. Thus the device can implement one or more playback settings which are specific to that authorised user.

An active noise control device includes a secondary path filter coefficient updating unit. The secondary path filter coefficient updating unit is configured to update a coefficient of a secondary path filter by using a coefficient of the secondary path filter after previous updating as a previous value, when a phase characteristic of the secondary path filter that sets an initial value as the coefficient and a phase characteristic of the secondary path filter that uses the previous value as the coefficient are not approximate to each other.

Various technologies described herein pertain to active noise cancellation in the interior of a vehicle. In exemplary embodiments, a microphone mounted on the vehicle outputs an audio signal indicative of noise emitted by a noise source. A computing system of the vehicle determines a position of the noise source based upon sensor signals output by sensors mounted on the vehicle. The computing system further determines a position of a passenger in the vehicle based upon a sensor mounted inside the vehicle. The computing system generates a complementary signal that is configured to attenuate the noise based upon the audio signal, the position of the noise source, and the position of the passenger. The complementary signal is then output by way of a speaker in the interior of the vehicle.

A system for reducing noise for a user includes a first detector configured to generate a first noise signal, wherein the first noise signal is a representation of a first noise that is transmitted to the user through a first sound pathway, and a second detector configured to generate a second noise signal, wherein the second noise signal indicates a second noise perceived by the user. The system also includes a processor configured to determine a noise correction signal based on the first noise signal and/or the second noise signal, and a speaker configured to generate a sound for reducing the noise based on the noise correction signal.

A global active noise control method for a rotorcraft, including: acquiring the acoustic pressure signal at a measuring point of the rotorcraft; predicting the holographic and global sound field of noise of the rotor; reconstructing the reverse sound field of the noise of the rotor; and performing adaptive sound field adjustment based on the optimal phase search.

A transfer function of a first variable filter is updated to output, from an output of a first seat microphone, a cancel sound that minimizes a level of a signal obtained by subtracting an output of an auxiliary filter that generates a correction signal for correcting a difference between positions of the first seat microphone and the first seat. In the ICC mode in which the uttered voice of the user in the first seat is output from a second seat speaker, a selector sets an uttered voice Dp output from the second seat speaker as an input to the first variable filter, and in the non-ICC mode, the selector sets an output sound of a second seat audio source output from the second seat speaker as an input to the first variable filter. The uttered voice Dp is generated by removing a component of the cancel sound from the output of the first seat microphone.

A sound state estimating unit detects surrounding sound at a timing at which a notification to a destination user occurs. A user state estimating unit detects a position of the destination user and positions of users other than the destination user at the timing at which the notification occurs. An output control unit controls output of the notification to the destination user at a timing at which it is determined that the surrounding sound detected by the sound state estimating unit is masking possible sound which can be used for masking in a case where the position of the destination user detected by the user state estimating unit is within a predetermined area.

An integrated circuit for implementing at least a portion of a personal audio device may include an output for providing an output signal to a transducer, wherein the output signal includes a pilot signal, a microphone input for receiving a microphone signal from a microphone indicative of an output of the transducer, and a processing circuit. The processing circuit may be configured to implement a pilot signal control to apply an adjustment to the pilot signal as necessary to maintain the pilot signal at a substantially constant magnitude regardless of proximity of the transducer to a pinna and implement a proximity determination block configured to determine proximity of the transducer to the pinna based on the adjustment.