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. 12, 1976
Filed:
Dec. 10, 1974
Jean-Michel Durand, Le Kremlin-Bicetre, FR;
Etienne Penicaud, Chaville, FR;
Abstract
The invention comes within the field of four-wire telephony. To avoid the closing of a loop between the two unidirectional channels, a half-echo suppressor is provided for each terminal, which comprises mainly a speech detector for the emitting channel, said speech detector having two operational modes: the first sends out a speech indicator signal based on the characteristics of amplitude and sign change on the emitting channel whereas the second compares the amplitude on the emitting channel and the amplitude on the receiving channel and is effective when the receiving channel is active. The invention applies more particularly to a PCM network in combination with a concentrator which uses the inactivity periods of the circuits.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile