An active vibration and noise control device robust against outside disturbances, and an active vibration and noise control circuit are provided. An adaptive control circuit of this active vibration and noise control device has autocorrelation value calculation units which calculate an autocorrelation value of an error signal or of a target signal, which is a reference signal or a standard signal, and a canceling output limiting unit which determines whether or not an autocorrelation value is less than an autocorrelation threshold value, and limits increases in the cancelling output if it is determined that the autocorrelation value is less than the autocorrelation threshold value.

An active vibration and noise control device robust against outside disturbances, and an active vibration and noise control circuit are provided. An adaptive control circuit of this active vibration and noise control device has a cross-correlation value calculation unit which calculates the cross-correlation value of error signals, and a canceling output limiting unit which determines whether or not the cross-correlation value is less than a cross-correlation threshold value, and limits increases in the cancelling output if it is determined that the cross-correlation value is less than the cross-correlation threshold value.

An automotive active brake noise damping system to actively damp braking noise perceivable in the passenger compartment of a motor vehicle comprising a braking system comprising a plurality of braking assemblies associated with wheels of the motor vehicle. The automotive active brake noise damping system comprises a sensory system to sense quantities that allow braking noise perceived in the passenger compartment of the motor vehicle and generated by the braking assemblies during braking to be estimated, an audio system to diffuse sounds in the passenger compartment of the motor vehicle, and an electronic control unit connected to the sensory system and the audio system, and programmed to control the audio system based on the quantities sensed by the sensor system to actively damp the braking noise perceived in the passenger compartment of the motor vehicle. The sensory system comprises vibration sensors, conveniently in the form of piezoelectric accelerators, which are applied to the braking assemblies to sense the amplitude of the vibrations generated by the braking assemblies during braking, and the electronic control unit is programmed to store a mathematical model, which correlates vibrations generated by the braking assemblies during braking with corresponding braking noise perceived in the passenger compartment of the motor vehicle and produced by the braking assemblies during braking, estimate the braking noise perceived in the passenger compartment of the motor vehicle and generated by the braking assemblies of the braking system during braking as a function of the vibrations generated by the braking assemblies during braking and sensed by the vibration sensors applied to the braking assemblies and of the stored mathematical model, compute an interfering sound to be diffused in the passenger compartment of the motor vehicle to damp the braking noise perceived in the passenger compartment of the motor vehicle and generated by the braking assemblies during braking, and control the audio system to cause it to diffuse the computed interfering sound.

An image capture device detects a wind whistle using two or more microphones. The image capture device includes a processor that obtains microphone signals from the two or more microphones and determines coherence values between the microphone signals across a frequency band. The processor determines a coherence value for each frequency bin of the frequency band. Based on a detection of an elevated coherence value in a frequency bin, the processor determines the presence of a whistle. The processor attenuates the frequency bin based on a determination that the elevated coherence value is above a threshold.

An automotive active brake noise damping system to actively damp braking noise perceivable in the passenger compartment of a motor vehicle comprising a braking system comprising a plurality of braking assemblies associated with wheels of the motor vehicle. The automotive active brake noise damping system comprises a sensory system to sense quantities that allow braking noise perceived in the passenger compartment of the motor vehicle and generated by the braking assemblies during braking to be estimated, an audio system to diffuse sounds in the passenger compartment of the motor vehicle, and an electronic control unit connected to the sensory system and the audio system, and programmed to control the audio system based on the quantities sensed by the sensor system to actively damp the braking noise perceived in the passenger compartment of the motor vehicle. The sensory system comprises vibration sensors, conveniently in the form of piezoelectric accelerators, which are applied to the braking assemblies to sense the amplitude of the vibrations generated by the braking assemblies during braking, and the electronic control unit is programmed to store a mathematical model, which correlates vibrations generated by the braking assemblies during braking with corresponding braking noise perceived in the passenger compartment of the motor vehicle and produced by the braking assemblies during braking, estimate the braking noise perceived in the passenger compartment of the motor vehicle and generated by the braking assemblies of the braking system during braking as a function of the vibrations generated by the braking assemblies during braking and sensed by the vibration sensors applied to the braking assemblies and of the stored mathematical model, compute an interfering sound to be diffused in the passenger compartment of the motor vehicle to damp the braking noise perceived in the passenger compartment of the motor vehicle and generated by the braking assemblies during braking, and control the audio system to cause it to diffuse the computed interfering sound.

The technology described herein can be embodied in a computer implemented method that includes detecting, by one or more processing devices, onset of an unstable condition in an active noise control system. The method also includes obtaining, responsive to detecting the onset of the unstable condition, updated filter coefficients for a system-identification filter configured to represent a transfer function of a secondary path of the active noise control system. The updated filter coefficients are generated using a set of multiple subband adaptive filters, wherein filter coefficients of each subband adaptive filter in the set are configured to adapt to changes in a corresponding portion of a frequency range associated with potential unstable conditions in the active noise control system. The method also includes programming the system identification filter with the updated coefficients to affect operation of the active noise control system.

The present disclosure provides a method for determining an arrangement of reference sensors for active road noise control (ARNC) in a vehicle with an automatic calibration system. The method includes mounting a plurality of vibrational sensors on a plurality of structure elements of the vehicle to generate a plurality of vibrational input signals and mounting at least one microphone inside a cabin of the vehicle to capture at least one acoustic input signal. The method further includes determining an arrangement of reference sensors from the plurality of vibrational sensors by determining a subset of vibrational sensors which sense the main mechanical inputs of road noise contributing to the at least one acoustic input signal.

A controller for the conference session generates a speaker signal for speakers in a conference room. The controller correlates the speaker signal with network timing information and generates speaker timing information. The controller transmits the correlated speaker signal and timing information to a mobile device participating in the conference session. The mobile device generates an echo cancelled microphone signal from a microphone of the mobile device, and transmits the echo cancelled signal back to the controller. The controller also receives array microphone signals associated with an array of microphones at known positions in the room. The controller estimates a relative location of the mobile device within the conference room. The controller dynamically selects as audio output corresponding to the mobile device location either the echo cancelled microphone signal from the mobile device or an echo cancelled array microphone signal associated with the relative location of the mobile device.

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 coherence based dynamic stability control system for a vehicle audio system may include at least one output sensor configured to transmit an output signal including a noise cancellation signal and an undesired noise signal, and at least one input sensor configured to transmit an input signal indicative of an acceleration of a vehicle. A processor may be programmed to control a transducer to output the noise cancellation signal based on at least one parameter, receive the input signal and the output signal, determine a coherence between the input signal and the output signal. The processor may be further programmed to determine whether the coherence exceeds a predefined coherence threshold, adjust the at least one parameter to generate an adjusted parameter and control the transducer to output an updated noise cancellation signal based on the parameter in response to the coherence failing to exceed the predefined coherence threshold.