Title:
ACTIVE NOISE CONTROL DEVICE
Document Type and Number:
Japanese Patent JP3500643
Kind Code:
B2
Abstract:
PURPOSE: To reduce noises which are not even correlated to reference signals by computing the coherence between reference signals, which indicates a noise generation condition, and residual noises and adjusting an active control process in accordance with the coherence.
CONSTITUTION: In an active noise control device, which reduces road noises transmitted into a compartment from the noise sources between road surfaces and wheels, a controller 10 outputs driving signals ym to a loudspeaker so as to compensate for the road noises transmitted to a compartment based on reference signals xk from an acceleration sensor, which is a noise generating condition detecting means, and residual noise signals e1 from a microphone. In this operation, a coherence computing section 12 of the controller 10 computes the coherence between the reference signals xk and the residual noise signals e1, a process content adjustment section 13 changes the convergence coefficients used in a filter coefficient update section 11 which updates the filter coefficients of an adaptive digital filter Wkm that generates the noise signals ym in accordance with a computed coherence γ2 (f) and adjusts the process contents.
Inventors:
Yoshiharu Nakaji
Application Number:
JP11050092A
Publication Date:
February 23, 2004
Filing Date:
April 28, 1992
Export Citation:
Assignee:
Nissan Motor Co., Ltd
International Classes:
G10K11/178; G10K11/16; H03H17/00; H03H17/04; H03H21/00; H04B3/04; (IPC1-7): G10K11/178; H03H17/04; H03H21/00
Domestic Patent References:
| JP56185A |
Attorney, Agent or Firm:
Tetsuya Mori (2 others)