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:
Oct. 05, 1999
Filed:
Dec. 10, 1996
Applicant:
Inventors:
Werner Boie, Strasbourg, FR;
Elias Bou Sleiman, Rennes, FR;
Assignee:
Thomson multimedia S.A., Boulogne Cedex, FR;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04N / ;
U.S. Cl.
CPC ...
348725 ; 455213 ; 455306 ; 455424 ; 364724011 ; 375350 ; 375229 ;
Abstract
The circuit for the digital filtering of IF intermediate frequency video signals comprises an A/D (analog/digital) converter and a Nyquist filter (N); an analog prefilter, suitable for selecting the desired channel, is placed upstream of the A/D converter. The Nyquist filter (N) is a digital filter placed downstream of the A/D converter, composed of two IIR filters (15, 16) placed in cascade, one (16) of these IIR filters being produced in non-causal form with spectrum conjugate to the other IIR filter (15) produced in causal form, and of an FIR filter (17) in series, for correcting the IIR filters.