Title:
ACTIVE TYPE NOISE CONTROL DEVICE
Document Type and Number:
Japanese Patent JP3449838
Kind Code:
B2
Abstract:
PURPOSE: To efficiently eliminate periodical noises like rotational engine noises.
CONSTITUTION: This device is constituted by having a microphone 1 measuring a sound pressure at a specific position, a loudspeaker 2 outputting a secondary sound eliminating a primary sound by interference at the microphone position, and a control circuit 3 generating the secondary sound and supply it to the loudspeaker with a tachometer pulse signal inputted as a reference signal and based thereon. The device is also provided with an adaptive controller 6 generating the secondary sound control signal by phase- and amplitude-modulations through an adaptive filter and supplying the secondary sound control signal to the loudspeaker, by using a reference signal generate by a reference signal generator 5 based on an output from a waveform shaping circuit 4.
Inventors:
Mitsuru Nakamura
Koji Abe
Hidekazu Nakano
Mitsuhide Sasaki
Koji Abe
Hidekazu Nakano
Mitsuhide Sasaki
Application Number:
JP26327695A
Publication Date:
September 22, 2003
Filing Date:
October 11, 1995
Export Citation:
Assignee:
株式会社日立製作所
International Classes:
B60R11/02; F01N1/00; G10K11/178; G10K15/00; H03H21/00; H04B3/23; (IPC1-7): G10K11/178; B60R11/02; F01N1/00; G10K15/00; H03H21/00
Domestic Patent References:
| JP6138886A |
Attorney, Agent or Firm:
Iwao Mishina
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