The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 09, 1994
Filed:
Aug. 27, 1992
Tsutomu Hamabe, Yokosuka, JP;
Akio Kinoshita, Fujisawa, JP;
Kazuhiro Doi, Yokohama, JP;
Kenichiro Muraoka, Yokosuka, JP;
Noriharu Sato, Katsuta, JP;
Nissan Motor Co., Ltd., Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An apparatus for reducing noise for an interior of enclosed space, e.g., a vehicular compartment using an FIR adaptive digital filter is disclosed in which a control circuit is provided which outputs drive signals to a plurality of loud speakers which generate control sounds to interfer with a noise sound propagated in the interior so that a performance function including terms of residual noise signals output from residual noise signal detecting microphones and drive signals to the loud speakers is minimized and contributivity of the drive signals to the performance function is changed according to an occurrence of divergence in the noise reducing apparatus.