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:
Jan. 31, 2023
Filed:
Jan. 04, 2022
Panasonic Intellectual Property Management Co., Ltd., Osaka, JP;
Mitsuhiro Tani, Osaka, JP;
Abstract
An active noise reduction device includes: a reference signal inputter; an adaptive filter; a μ adjuster that calculates a step size parameter by multiplying a reference value for the step size parameter by a correction coefficient that is proportional to a reciprocal of a first representative input value that indicates a signal level of the reference signal in a first predetermined period; a filter coefficient updater that updates adaptive filter coefficient W by using the step size parameter calculated; and a determiner. When it is determined that a second representative input value is greater than a threshold value, at least one of the adaptive filter or the filter coefficient updater is transitioned from a normal state to a restriction state in which an effect of reducing noise is smaller than in the normal state.