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:
May. 27, 2014
Filed:
May. 23, 2011
Moulay Fadili, Paris, FR;
Labib Zargouni, Paris, FR;
Moulay Fadili, Paris, FR;
Labib Zargouni, Paris, FR;
Alcatel Lucent, Paris, FR;
Abstract
The proposed echo canceller comprises:—an adaptive filter for receiving a signal affected by an echo, and for supplying a filtered signal that is an estimate of the echo;—a subtractor for subtracting this estimate from the received signal and supplying a residual signal;—means for detecting () a ring back tone in said residual signal;—means for blocking () the received signal and replacing it by a locally generated ring back tone if a ring back tone is detected in the received signal;—a timer to determine a time period;—and means (-) for, during said time period, replacing the residual signal by some synthetic comfort noise when there is no ring back tone.