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. 17, 2013
Filed:
Nov. 29, 2007
Anders Eriksson, Uppsala, SE;
Per Ahgren, Knivsta, SE;
Anders Eriksson, Uppsala, SE;
Per Ahgren, Knivsta, SE;
Telefonaktiebolaget LM Ericsson (Publ), Stockholm, SE;
Abstract
A method and arrangement for cancelling echoes in a communication terminal () during a voice call with an opposite party. The communication terminal () comprises an echo cancelling unit () adapted to produce an estimate of echo information in received speech signals coming from a microphone in the communication terminal (), and subtract the estimate from the received microphone signals, before being transmitted to the opposite party. The estimate is produced based on down-sampled received microphone signals and down-sampled received speech signals from the opposite party. The down-sampled speech signals from the opposite party are filtered in a digital filter (), and the output signals from the filter () are up-sampled to form the estimate. Performing echo cancelling based on down-sampled speech signals from the opposite party and down-sampled microphone signals, requires a reduced amount of processing capacity of the communication terminal, still resulting in a sufficiently high quality echo cancellation.