Abstract: An active noise control (ANC) system includes a speaker and one or more processors. The one or more processors implement an adaptive subband filtered reference control algorithm that applies thresholds to reference and error feedback signal paths such that, in response to a series of broadband non-Gaussian impulsive reference signals indicative of road noise in the vehicle having an audible frequency range of 20 Hz to 20 kHz, weight coefficients defining an adaptive filter of the control algorithm converge and permit the ANC system to partially cancel the road noise via output of the speaker.

Abstract: An active noise control (ANC) system includes a speaker and one or more processors programmed to implement a delayless subband filtered-x least mean square control algorithm. The algorithm includes a variable bandwidth discrete Fourier transform filter bank having a number of subbands such that the system, in response to a broadband white noise reference signal indicative of road noise in the vehicle, exhibits a uniform gain spectrum across a frequency range defined by the subbands and partially cancels the road noise via output of the speaker.

Abstract: An active noise control (ANC) system includes a speaker and one or more processors programmed to implement a delayless subband filtered-x least mean square control algorithm. The algorithm includes a variable bandwidth discrete Fourier transform filter bank having a number of subbands such that the system, in response to a broadband white noise reference signal indicative of road noise in the vehicle, exhibits a uniform gain spectrum across a frequency range defined by the subbands and partially cancels the road noise via output of the speaker.

Abstract: An active noise control (ANC) system includes a speaker and one or more processors. The one or more processors implement an adaptive subband filtered reference control algorithm that applies thresholds to reference and error feedback signal paths such that, in response to a series of broadband non-Gaussian impulsive reference signals indicative of road noise in the vehicle having an audible frequency range of 20 Hz to 20 kHz, weight coefficients defining an adaptive filter of the control algorithm converge and permit the ANC system to partially cancel the road noise via output of the speaker.

Abstract: A multiple error filtered-x least mean square (MEFxLMS) algorithm using a channel equalization virtual secondary path for an active noise control/cancellation (ANC) system for treating noise in a Multiple-Input Multiple-Output (MIMO) system. The channel equalization technique equalizes amplitude levels of the estimated response of all primary channels to overcome limitations caused by the frequency dependent property of standard filtered-x least mean square (FxLMS) algorithm, reduce the variation of convergence speed existed in the multiple channels, and improve the overall performance of the control system. The convergence property of the algorithm is analyzed in the frequency domain.

Abstract: A multiple error filtered-x least mean square (MEFxLMS) algorithm using a channel equalization virtual secondary path for an active noise control/cancellation (ANC) system for treating noise in a Multiple-Input Multiple-Output (MIMO) system. The channel equalization technique equalizes amplitude levels of the estimated response of all primary channels to overcome limitations caused by the frequency dependent property of standard filtered-x least mean square (FxLMS) algorithm, reduce the variation of convergence speed existed in the multiple channels, and improve the overall performance of the control system. The convergence property of the algorithm is analyzed in the frequency domain.