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:
Feb. 06, 2001
Filed:
Mar. 02, 1998
Shinya Muraoka, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
In an echo canceler, a first adaptive filter circuit calculates first tap coefficients using a first convergence coefficient, and generates a first pseudo echo signal, and a first subtracter subtracts the first pseudo echo signal from a transmitting signal to generate a first error signal. A second adaptive filter circuit calculates second tap coefficients using a second convergence coefficient, and generates a second pseudo echo signal, and a second substrate subtracts the second pseudo echo signal from the transmitting signal to generate a second error signal. A control circuit selects one set of the first tap coefficients and the second tap coefficients in accordance with a received signal, the transmitting signal, and the first and second error signals. A third adaptive filter circuit generates a third pseudo echo signal in accordance with the set of tap coefficients selected by the control circuit and the received signal, and a third subtracter subtracts the third pseudo echo signal from the transmitting signal to generate a third error signal.