An active noise cancellation system includes a sensor operable to sense environmental noise and generate a corresponding reference signal, a fixed noise cancellation filter including a predetermined model of the active noise cancellation system operable to generate an anti-noise signal, and a tunable noise cancellation filter operable to modify the anti-noise signal in accordance with stored coefficients, wherein the tunable noise cancellation filter is further operable to modify the stored coefficients in real-time based on user feedback and generate a tuned anti-noise signal that models tunable deviations from the predetermined noise model. A graphical user interface is operable to receive user adjustments of tunable parameters in real-time, the tunable parameters corresponding to at least one of the stored coefficients.

Method and system for active reduction of a predefined audio acoustic signal (AAAS), also referred to as noise, in a quiet zone, without interfering undefined acoustic noise signals within as well as outside the quiet zone, by generating accurate antiphase AAAS signal. The accuracy of the generated antiphase AAAS is obtained by employing a unique synchronization signal(s) (SYNC) which is generated and combined with the predefined AAAS. The combined signal is electrically transmitted (referred to as the electric channel) to a processing quieting component. Simultaneously, the generated SYNC signal is acoustically broadcasted near the predefined AAAS and merges with it. A microphone in the quiet zone receives the merged acoustic signals that arrive via the air (referred to as the acoustical channel) to the quiet zone and a receiver in the quieting component receives the combined electrical AAAS and SYNC signal that arrive wire or wireless to the quiet zone. In the quiet component the SYNC is detected from both electrical and acoustical channels, the detected SYNC signals with the electrically received AAAS signal are used to calculate the timing and momentary amplitude for generating an accurate acoustic antiphase AAAS signal to cancel the acoustic predefined AAAS. By continuously and periodically updating the SYNC signal enables to dynamically evaluate acoustical environmental distortions that might appear due to echo, reverberations, frequency non-linear response, or due to other distortions mechanisms.

A noise-reduction control method includes performing frequency-domain weighting and temporal-domain weighting to a noise signal collected at current time to obtain a weighted energy. Judging whether active noise-reduction control is needed based on the weighted energy; calculating an energy value of a first sub-band and an energy value of a second sub-band of the noise signal collected by the feedforward microphone at the current time, wherein the first sub-band and the second sub-band are determined based on a feedforward noise-reduction curve and a feedback noise-reduction curve of the earphone, respectively. Determining a feedforward noise-reduction amount and a feedback noise-reduction amount based on the energy value of the first sub-band and the energy value of the second sub-band, respectively. Controlling the earphone to perform feedforward noise reduction based on the feedforward noise-reduction amount, and controlling the earphone to perform feedback noise reduction based on the feedback noise-reduction amount.

The disclosure includes a headset comprising one or more earphones including one or more sensing components. The headset also includes one or more voice microphones to record a voice signal for voice transmission. The headset also includes a signal processor coupled to the earphones and the voice microphones. The signal processor is configured to employ the sensing components to determine a wearing position of the headset. The signal processor then selects a signal model for noise cancellation. The signal model is selected from a plurality of signal models based on the determined wearing position. The signal processor also applies the selected signal model to mitigate noise from the voice signal prior to voice transmission.

An active noise control (ANC) circuit is used for generating an anti-noise signal, and has a plurality of filters including at least one first filter and at least one second filter. The at least one first filter generates at least one first filter output, wherein each of the at least one first filter has a first filter type. The at least one second filter generates at least one second filter output, wherein each of the at least one second filter has a second filter type different from the first filter type. The anti-noise signal is jointly controlled by the at least one first filter output and the at least one second filter output. The at least one first filter and the at least one second filter are connected in a parallel fashion.

A first input signal captured by one or more sensors associated with an ANR headphone is received. A frequency domain representation of the first input signal is computed for a set of discrete frequencies, based on which a set of parameters is generated for a digital filter disposed in an ANR signal flow path of the ANR headphone, the set of parameters being such that a loop gain of the ANR signal flow path substantially matches a target loop gain. Generating the set of parameters comprises: adjusting a response of the digital filter at frequencies (e.g., spanning between 200 Hz-5 kHz). A response of at least 3 second order sections of the digital filter is adjusted. A second input signal in the ANR signal flow path is processed using the generated set of parameters to generate an output signal for driving the electroacoustic transducer of the ANR headphone.

The present method comprises: providing a feedforward microphone outside of each earphone of the active noise-reduction earphones; detecting an amount of external noise by using the feedforward microphone; calculating a weighted energy of a noise signal; and determining whether it is needed to activate the active noise-reduction system based on the weighted energy. When the active noise-reduction control is needed, calculating energy values of two sub-bands, corresponding to the feedforward noise-reduction amount and the feedback noise-reduction amount respectively, in the noise signal, thereby determining the noise-reduction amounts of the feedforward noise reduction system and the feedback noise-reduction system, and controlling the earphone to perform corresponding feedforward noise reduction and feedback noise reduction. Compared with the existing active noise-reduction technologies with a fixed noise reduction, the present invention can optimize the noise-reduction effect.

An active noise reduction system includes a canceling sound output device configured to output a canceling sound for canceling a noise, a noise signal generator configured to generate noise signals based on the noise, and a controller configured to control the canceling sound output device based on the noise signals, wherein the controller is configured to acquire buffer data in which the noise signals are stored in a time series, generate a plurality of divided data by dividing the buffer data, calculate a correlation value of the buffer data based on the plurality of divided data, detect presence/absence of disturbance mixed in the buffer data based on the correlation value, and switch control over the canceling sound output device according to the presence/absence of the disturbance mixed in the buffer data.

A feedforward ambient noise reduction arrangement includes, within a housing, a loudspeaker device for directing sound energy into an ear of a listener. Disposed externally of the housing, and positioned to sense ambient noise on its way to the listener's ear, are plural microphone devices capable of converting the sensed ambient noise into electrical signals for application to the loudspeaker to generate an acoustic signal opposing the ambient noise. Importantly, the overall arrangement is such that the acoustic signal is generated by said loudspeaker means in substantial time alignment with the arrival of said ambient noise at the listener's ear.

The present method comprises: providing a feedforward microphone outside of each earphone of the active noise-reduction earphones; detecting an amount of external noise by using the feedforward microphone; calculating a weighted energy of a noise signal; and determining whether it is needed to activate the active noise-reduction system based on the weighted energy. When the active noise-reduction control is needed, calculating energy values of two sub-bands, corresponding to the feedforward noise-reduction amount and the feedback noise-reduction amount respectively, in the noise signal, thereby determining the noise-reduction amounts of the feedforward noise reduction system and the feedback noise-reduction system, and controlling the earphone to perform corresponding feedforward noise reduction and feedback noise reduction. Compared with the existing active noise-reduction technologies with a fixed noise reduction, the present invention can optimize the noise-reduction effect.