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:
Jun. 03, 2003
Filed:
Sep. 14, 1999
Applicant:
Inventor:
Shinichi Kawada, Tokyo, JP;
Assignee:
Oki Electric Industry, Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04M 9/08 ;
U.S. Cl.
CPC ...
H04M 9/08 ;
Abstract
To remove the echo of a received signal from a local input signal, an echo canceler adaptively estimates the transfer characteristics of the echo path. When a double-talk condition is detected, the echo canceler reverses the adaptation process and returns to a set of estimated transfer characteristics that were in use before the double-talk condition began. Imperfect echo cancellation due to incorrect estimation caused by double-talk is thus prevented inexpensively.