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:
Jun. 04, 1996
Filed:
Jun. 08, 1993
Masaichi Akiho, Iwaki, JP;
Nozomu Saito, Iwaki, JP;
Tatsuo Owaki, Iwaki, JP;
Kunio Miyauchi, Wako, JP;
Akira Suto, Wako, JP;
Alpine Electronics Inc., , JP;
Abstract
A noise-canceling apparatus includes a canceling-sound generating source for outputting a canceling sound, a sensor for sensing a composite sound that is a composite of noise and the canceling sound at a noise-canceling point, a noise-canceling controller, to which a composite-sound signal and a reference signal conforming to noise generated by a noise source are inputted, for generating a noise-canceling signal by executing adaptive signal processing so as to cancel out the noise at the noise-canceling point using these signals and inputting the noise-canceling signal to the canceling-sound generating source, and a frequency-characteristic correcting unit provided on the input side of an adaptive filter, which constructs the noise-canceling controller, and having a frequency characteristic that is substantially symmetrical, about a 0 dB line, with respect to the frequency characteristic of a canceling-sound propagation system. The noise-canceling controller executes adaptive signal processing with a signal obtained by inputting the reference signal to the frequency-characteristic correcting unit being adopted as a true reference signal.