An active vibration noise control system is applied to a vehicle provided with an EPS motor to change behavior of the vehicle. The active vibration noise control system includes an ANC processor configured to receive acoustic information at a predetermined position in a vehicle compartment as an error signal and control a vibration noise based on a reference signal correlate with the vibration noise and the error signal that is received and an inverse electromotive force information receiving section receiving information on an inverse electromotive force induced on the EPS motor by behavior change of the vehicle. The ANC processor utilizes as a reference signal the information on the inverse electromotive force received by the inverse electromotive force information receiving section. The active vibration noise control system actively controls the vibration noise generated in the vehicle.

An active noise control device includes: a control target signal extractor for extracting a signal component of a control target frequency from an error signal as a control target signal which is a complex-valued signal having a real part and an imaginary part; a control signal generator for generating a control signal for controlling a control actuator, by signal-processing the control target signal through a control filter; and a control filter coefficient updater for successively and adaptively updating the coefficient of the control filter.

An audio processing system is configured to process an audio signal representing sound waves originating from at least one vehicle system disposed on a vehicle. The audio processing system includes a controller configured to receive the audio signal from a microphone. The controller processes the audio signal to generate a frequency domain representation of the audio signal. The controller also receives a first operating signal indicating an operating state of a first said vehicle system. The controller decomposes the frequency domain representation of the audio signal in dependence on the first operating signal to identify a first audio profile associated with the operation of the first vehicle system. Aspects of the present invention also relate to a vehicle including an audio processing system.

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.

In accordance with an embodiment, a method of measuring a gas concentration includes modulating an infrared light source according to a frequency-hopped sequence or according to a pulse sequence, receiving a microphone signal from an output of a microphone acoustically coupled to a gas exposed to infrared light produced by the infrared light source; bandpass filtering the microphone signal using a bandpass filter; and estimating the gas concentration from the filtered microphone signal.

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.

In at least one embodiment, a system for performing active noise cancelation in a vehicle is provided. The system includes an adaptive filter and an adjustment controller. The adaptive filter is configured to control a loudspeaker to generate anti-noise to cancel undesired noise in the vehicle. The adjustment controller is programmed to receive a reference signal from one or more accelerometers. Each reference signal includes a frequency that is indicative of a force acting on a portion of the vehicle. The adjustment controller is programmed to compare the frequency to a predetermined frequency threshold and to control a first filter to filter to the frequency based on the comparison of the frequency to the predetermined frequency threshold. The adjustment controller is programmed to transmit a filtered reference signal to the adaptive filter to generate the anti-noise without influence of the frequency of the reference signal.

A system and method for accurately estimating engine noise at a virtual microphone location, such as an occupant's ear position, in an acoustic space in order to enhance performance of an Engine Order Cancellation (EOC) system is provided. A set of weights and transfer functions that are dependent on various vehicle parameters, such as frequency, load, and speed, may be employed to estimate noise at a position where there are no physical microphones present. The accurate estimation of engine noise at virtual location, such as an occupant's ear position, may be achieved using a frequency dependent weighted sum of filtered and unfiltered error signals measured at microphones mounted at various locations inside an acoustic space, such as a vehicle cabin, which may not be located near virtual location.

The present disclosure relates a capturing device of remote warning sound component which utilizes an audio pick-up device receives a remote sound signal in a remote range, and a processor generates a warning sound component through amplifying a sound feature point audio in a sound component according to warning voiceprint data and generates non-warning sound components through suppressing or shielding the sound feature point audio in the other sound components according to non-warning voiceprint information. Then the processor combines the warning sound component and the non-warning sound components to generate an output sound signal, allowing a speaker to output the output sound signal. Accordingly, the capturing device of the present disclosure provides instantly warning sound which is received (e.g. sound of car engine) from a remote range and outputs to allow the user in an early alert state, then reducing the probability of incident occurs thereby.

Methods of operating headphones may involve filtering an input signal into a first filtered input signal and a second filtered input signal utilizing a filter. The second filtered input signal may be sent directly to a tactile vibration driver and tactile vibrations may be produced. A fixed, predetermined inverse transfer function may be applied to the first filtered input signal, generating an anti-wave signal. The anti-wave signal may be summed with the first filtered input signal, generating an output signal. Alternatively, a fixed, predetermined transfer function may be applied to the first filtered input signal, generating a modified input signal. The modified input signal may be subtracted from the first filtered input signal, generating an output signal. Audio sound waves may be produced with an acoustic driver responsive to the output signal, reducing effects of incidental acoustic noise generated by the tactile vibration driver.