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. 16, 1987
Filed:
Oct. 04, 1984
Centre de Recherche Industrielle du Quebec, Quebec, CA;
Abstract
A multiple frequency adaptive filter system for filtering undesired periodic and/or correlated interference signals contained in the same frequency band as a desired input signal. The filter system is capable of filtering at least two sinusoidal interference signals and incorporates a negative feedback loop having a transfer function of that of narrow band-pass multiple filter. The feedback loop using interference frequencies generates a corresponding interference enhanced output signal. This enhanced output signal is combined with the input signal whereby to produce an error signal which corresponds to the desired signal contained in the input frequency band. A double or quadruple filter system is also described as examples of the present invention. The filter system is suitable for removing modulated sinusoidal interference and particularly for reducing TV co-channel interference.