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:
Jun. 22, 1998
Alexander Goldin, Haifa, IL;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method and device for adaptive echo cancellation in a voice communication system wherein a reference signal x is sent over the system from a transmitting device and comprising an adaptive filter for removing any echo signal from a primary signal d received in answer to reference signal x, and said adaptive filter having a plurality of coefficients the value of which at each time n being computed from the value of the same coefficient at time n−1 modified by a normalization factor depending upon the energy of said reference signal and provided by a normalization factor controlling unit. The normalization factor is the maximum value between a first value representing the energy of reference signal x at time n and a second value depending on a value of the normalization factor previously stored during a preceding predetermined interval time multiplied by an attenuation factor less than 1.