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:
Aug. 25, 1981
Filed:
Apr. 23, 1979
Jean P Houdard, Orsay, FR;
Le Materiel Telephonique, Boulogne-Billancourt, FR;
Abstract
This invention relates to digital devices for spectral analysis. Signal x(t) of spectrum X(f), sampled at frequency 1/T and encoded, is processed by a temporal digital filter having a width NT followed by one or more perfect digital resonators in parallel, each tuned to a specific predetermined frequency f.sub.p and possessing two outputs, one being the 'sine' output and the other being the 'cosine' output on which the digital signals X(f.sub.p) sin 2.pi.f.sub.p kT and X(f.sub.p) cos 2.pi.f.sub.p kT are obtained after time NT, from which the value X.sup.2 (f.sub.p) can be formed by conventional digital processing. Application to encoded multifrequency signal receivers used in telephone switching.