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:
Nov. 26, 2002
Filed:
Oct. 05, 1998
Cyril Bertrand, Paris, FR;
Philippe Sehier, St Germain en Laye, FR;
Alcatel, Paris, FR;
Abstract
The invention relates to apparatus for filtering, decimating and transposing into baseband, the apparatus being of the entirely digital type, and serving both to extract and transpose into baseband one of the channels, referred to as the “channel of interest”, of a frequency multiplex of channels, and also to reduce the oversampling factor of said channel of interest, each channel being associated with a distinct carrier. The said apparatus comprising at least two stages in cascade ( to ), each stage comprising filter means ( ) and decimation means ( ), said filter means being placed upstream from said decimation means and enabling a portion of the spectrum to be purged at locations where the decimation means produce aliasing. According to the invention, each stage ( to ) also comprises transposition means ( ) placed upstream from said filter means ( ) and associated with a transposition frequency (f ) previously selected from a set of N possible distinct transposition frequencies so as to transpose the carrier (p ) associated with said channel of interest as close as possible to zero frequency.