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. 23, 1990
Filed:
Mar. 22, 1989
Applicant:
Inventor:
Bertrand Salle, Paris, FR;
Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04B / ;
U.S. Cl.
CPC ...
370 321 ; 379411 ;
Abstract
An echo canceller for cancelling a variable-phase echo signal is connected between two one-way send and receive paths coupled by means of a coupling circuit (6) to a two-way path. This echo canceller comprises an adaptive filter (92) cooperating with a phase shifter (95) for forming a replica of the echo signal, and a subtractor (72) inserted in the receive path for producing a difference signal between the echo signal and its replica. This canceller further comprises a suppressing circuit for suppressing a d.c. component (300) of the difference signal, which circuit is designed for supplying an adjusting quantity in the direction of the adaptive filter and the phase sifter.