US 12,361,919 B2
Instability detection and adaptive-adjustment for active noise cancellation system
Tao Feng, Novi, MI (US); and Kevin J. Bastyr, Franklin, MI (US)
Assigned to HARMAN INTERNATIONAL INDUSTRIES, INCORPORATED, Stamford, CT (US)
Appl. No. 18/278,732
Filed by HARMAN INTERNATIONAL INDUSTRIES, INCORPORATED, Stamford, CT (US)
PCT Filed Feb. 26, 2021, PCT No. PCT/US2021/019765
§ 371(c)(1), (2) Date Aug. 24, 2023,
PCT Pub. No. WO2022/182351, PCT Pub. Date Sep. 1, 2022.
Prior Publication US 2024/0203392 A1, Jun. 20, 2024
Int. Cl. G10K 11/178 (2006.01)
CPC G10K 11/17817 (2018.01) [G10K 11/17825 (2018.01); G10K 11/17883 (2018.01); G10K 2210/12821 (2013.01); G10K 2210/3026 (2013.01); G10K 2210/3027 (2013.01); G10K 2210/3028 (2013.01); G10K 2210/3044 (2013.01)] 17 Claims
OG exemplary drawing
 
1. An active noise cancellation (ANC) system comprising:
at least one loudspeaker to project anti-noise sound within a passenger cabin of a vehicle in response to receiving an anti-noise signal;
at least one microphone to provide an error signal indicative of noise and the anti-noise sound within the passenger cabin;
an adaptive filter controller programmed to:
filter the error signal to obtain a noise reduction ratio, and
adjust a step size parameter based on a comparison of the noise reduction ratio to a noise threshold; and
a controllable filter to generate the anti-noise signal based on the adjusted step size parameter, and
wherein the adaptive filter controller is further programmed to:
filter the error signal using a transfer function to obtain an estimated virtual microphone error signal; and
filter the estimated virtual microphone error signal to obtain the noise reduction ratio.