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.

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.

An active noise cancellation system has a secondary path including a loudspeaker configured to output an anti-noise signal to cancel noise in a noise cancellation zone, and an error microphone configured to sense sound in the noise cancellation zone. The ANC system further includes a logic device configured to adaptively generate the anti-noise signal for playback through the loudspeaker based at least in part on a feedback signal from the error microphone and identify a user of the active noise cancellation system based, at least in part, on a measured frequency response of the secondary path. The logic device is further configured to identify the user of the active noise cancellation system through a comparison of the measured frequency response of the secondary path to stored models and may be configured to execute a new user enrollment process, store user profiles, and/or switch between in-ear and open-air states.

A system for evaluating a noise management module of a vehicle includes a controller programmed to filter speaker signals from the noise management module using an auralization model to produce auralized sound signals that create a spatial effect to simulate sound in the vehicle at a predetermined position within the vehicle that is different than the positions corresponding to microphones used by the noise management module.

A method for reducing the power of an acoustic primary noise signal (d.sub.m(n)) at one or more control positions in a vehicle passenger compartment using an adaptive filter. The method comprising to compare a mean correlation coefficient (γ.sub.m(n)) between an electrical error signal (e.sub.m(n) and a modelled secondary anti-noise signal ŷ.sub.m(n) with at least one predefined threshold (α, β).

A system performs pole-zero or IIR modeling and estimation of an inter-microphone transfer function between first and second microphones that output respective first and second microphone signals. The system includes a first adaptive FIR filter to which the first microphone signal is provided, a delay element that delays the second microphone signal by a predetermined delay amount, and a second adaptive FIR filter to which the delayed second microphone signal is provided. A first coefficient of the second adaptive FIR filter is constrained to a fixed non-zero value. The filters are jointly adapted to minimize an error signal that is a difference of the two filters outputs. The delay is small: approximately the acoustic propagation delay between the two microphones and is not determined by the environmental reverberation characteristics. The error signal may serve as a noise reference in a noise canceller, for implementing far-field beamforming with low delay.

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.

A method of identifying a system, the method comprising: obtaining an indication of background noise present at the system; generating a probe signal based on the indication; applying the probe signal to the system; estimating a response of the system to the probe signal; and identifying the system based on the measured response and the probe signal, wherein the probe signal comprises a whitening component configured to whiten noise in the estimated response due to the background noise present at the system.

A noise cancellation system for a noise cancellation enabled audio device comprises a first noise filter and a second noise filter, each being designed to process a noise signal, a combiner and an adaptation engine. The first noise filter has a first fixed frequency response matched to a high leakage condition of the audio device. The second noise filter has a second fixed frequency response matched to a low leakage condition of the audio device. The combiner is configured to provide a compensation signal based on a combination of an output of the first noise filter amplified with a first adjustable gain factor and an output of the second noise filter amplified with a second adjustable gain factor. The adaptation engine is configured to estimate a leakage condition of the audio device based on an error noise signal and to adjust at least one of the first and the second adjustable gain factors based on the estimated leakage condition.

A method for reducing the power of an acoustic primary noise signal (d.sub.m(n)) at one or more control positions in a vehicle passenger compartment using an adaptive filter. The method comprising to compare a mean correlation coefficient (.sub.m(n)) between an electrical error signal (e.sub.m(n) and a modelled secondary anti-noise signal .sub.m(n) with at least one predefined threshold (, ).