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:
May. 28, 1985
Filed:
Nov. 04, 1982
Jean M Raulin, Noisy le Sec, FR;
Georges Bonnerot, Les Ulis, FR;
Abstract
In this transmission system using differential PCM, the local decoder, inporated in the loop of the encoder, and the remote decoder comprise identical filters (5) and (15) each constituted by a cascade arrangement of several filtering sections (F.sub.1 -F.sub.N) of the first and/or of the second order; each section may have one or two controllable coefficients, which are modified at each sampling instant by a modification term which depends upon the product of the difference signal (e) produced in the encoder and the gradient of the difference signal (e) with respect to the controllable coefficient. When the filtering sections (F.sub.1 -F.sub.N) are recursive, the gradients are obtained by applying a signal corresponding to the difference signal (e) to identical recursive sections (F'.sub.1 -F'.sub.N). When non-recursive filtering sections (H.sub.1 -H.sub.L) are used, the gradient calculation sections (H'.sub.1 -H'.sub.L) are recursive with a transfer function inverse to that of the sections (H.sub.1 -H.sub.L).