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:
Sep. 03, 2013
Filed:
Mar. 09, 2011
Shinji Nakatsuka, Kanagawa-ken, JP;
Kazuhiro Oda, Kanagawa-ken, JP;
Shinji Nakatsuka, Kanagawa-ken, JP;
Kazuhiro Oda, Kanagawa-ken, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
An echo cancellation circuit in a full duplex two-way communication system comprising: an input/output terminal; a subtractor having a positive and a negative input terminals, in which a first transmission signal is inputted to the negative input terminal as a pseudo echo signal, the first transmission signal is inputted through an output buffer to the positive input terminal as an echo signal, the pseudo echo signal inputted to the negative input terminal is subtracted from the echo signal inputted to the positive input terminal; and a result of the subtraction is outputted; and an echo cancellation error reducing unit having a D/A converter at an input side or an output side of the subtractor.