A noise canceler includes a signal obtaining unit that obtains an observation signal obtained by sampling vibration of an apparatus; a signal delay unit that obtains a delay signal by delaying the observation signal obtained by the signal obtaining unit; and a Kalman filter processing unit that applies, to the observation signal and the delay signal, a Kalman filter that adapts a filter coefficient so as to reduce a residual signal between the observation signal and an estimated signal estimated based on the observation signal and the delay signal by an adaptive filter that incorporates the Kalman filter, and outputs the residual signal.

A method for audio signal noise cancellation is provided. In response to current noise cancellation coefficients being required to be updated to new noise cancellation coefficients, the digital signal processor calculates the new noise cancellation coefficients and writes the new noise cancellation coefficients into an idle storage module in the at least two storage modules, and the digital signal processor sends an update request for updating the noise cancellation coefficients to the active noise cancellation module. The update request carries position information configured to indicate a position of the storage module to which the new noise cancellation coefficients is written. The active noise cancellation module reads the new noise cancellation coefficients in the storage module indicated by the position information based on the position information carried in the update request, and performs noise cancellation processing according to the new noise cancellation coefficients after a current noise cancellation processing cycle ends.

Methods, systems, and apparatuses are disclosed for reducing sound level, by providing enclosures comprising enclosure walls having integral tunable resonator cavities, and reducing sound levels within the enclosure in response to detected sound levels outside of the enclosure.

The invention involves the employment of a non-acoustical transducer embodying one non-acoustical sensor (or more non-acoustical sensors) which is adapted to sense acoustical sounds. The invention for realizing an Active Noise Cancellation device involves the replacement of the acoustic microphone (or microphones) in the said device with the aforesaid one non-acoustical sensor (or more sensors).

A vehicle-implemented, adaptive noise-cancellation system responsive to entertainment audio is provided. The noise-cancellation system uses reference signal from a reference sensor, such as an accelerometer, to generate a noise-cancellation signal to destructively interfere with road noise in the vehicle cabin. A first set of entertainment audio thresholds triggers the system to enable or disable adaptation of an adaptive filter of the noise-cancellation system. A second set of entertainment audio thresholds triggers the system to enable, attenuate, or disable the noise-cancellation signal. As the entertainment audio increases, the system first disables the adaptation of the adaptive filter, then attenuates the noise-cancellation signal, then completely disables the noise-cancellation signal. Conversely, as the entertainment audio decreases, the system first enables the noise-cancellation signal, then reduces the attenuation (thereby increasing the amplitude) of the noise-cancellation signal, and then enables the adaptation of the adaptive filter.

An integrated circuit for implementing at least a portion of a personal audio device may include an output for providing a signal to a transducer including both a source audio signal for playback to a listener and an anti-noise signal for countering the effects of ambient audio sounds in an acoustic output of the transducer, a reference microphone input for receiving a reference microphone signal indicative of the ambient audio sounds, an error microphone input for receiving an error microphone signal indicative of the output of the transducer and the ambient audio sounds at the transducer, and a processing circuit configured to implement an adaptive infinite impulse response filter having a response that generates the anti-noise signal to reduce the presence of the ambient audio sounds at the error microphone and implement a coefficient control block that shapes the response of the adaptive infinite impulse response filter in conformity with the error microphone signal by generating coefficients that determine the response of the adaptive infinite impulse response filter in order to minimize the ambient audio sounds at the error microphone, wherein the coefficient control block selects the coefficients from a library of filter entries, each filter entry of the library of filter entries defining a respective response for the adaptive infinite impulse response filter.

An audio system for an ear mountable playback device comprises a speaker, an error microphone predominantly sensing sound being output from the speaker and a feed-forward microphone predominantly sensing ambient sound. The audio system further comprises a voice activity detector which is configured to record a feed-forward signal from the feed-forward microphone. Furthermore, an error signal is recorded from the error microphone. A detection parameter is determined as a function of the feed-forward signal and the error signal. The detection parameter is monitored and a voice activity state is set depending on the detection parameter.

An electronic system includes a fan module, an embedded controller, a reference microphone, an error microphone, an active noise cancellation controller, and a micro speaker module. The reference microphone is configured to output a wide-band noise signal associated with the operation of the fan module. The error microphone is configured to output an error signal by detecting the noise level during the operation of the electronic system. According to the wide-band noise signal, the error signal and the fan information provided by the embedded controller, the active noise cancellation controller calculates the narrow-band noises and the wide-band noises generated by the fan module, and drives the micro speaker module accordingly for providing a noise cancellation signal. The error signal may be reduced to zero by adaptively adjusting the noise cancellation signal for canceling the noises generated during the operation of the electronic system.

A method is disclosed, the method comprising obtaining at least one first information indicative of audio data gathered by at least one first microphone, and at least one second information indicative of audio data gathered by at least one second microphone; determining a differential information indicative of one or more differences between at least two pieces of information, wherein the differential information is determined based, at least in part, on the at least one first information and the at least one second information; and compensating of an impact onto the audio data, wherein audio data of the first information and/or the second information is compensated based, at least in part, on the determined differential information. Further, an apparatus, and a system are disclosed.

The present invention provides an improved noise separation hybrid type ANC system, which includes a reference audio receiving device, an error audio receiving device, an audio output device, and an audio processing device. The audio processing device includes a feed-forward noise cancellation filter module, a feedback noise cancellation filter module, a mixer, a noise shaper, a first infinite impulse response filter, and a second infinite impulse response filter. When the noise bandwidth detector detects irregular noise, it adjusts the coefficient of the first infinite impulse response filter to set it as a low-pass filter; when regular noise is detected, the coefficient of the second infinite impulse response filter is adjusted to set it as a band-pass filter.