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:
Mar. 24, 2009
Filed:
Jan. 27, 2005
Renee Johnston, Dunrobin, CA;
Mirjana Popovic, Ottawa, CA;
Dieter Schulz, Dunrobin, CA;
Jan Radecki, Ottawa, CA;
Renee Johnston, Dunrobin, CA;
Mirjana Popovic, Ottawa, CA;
Dieter Schulz, Dunrobin, CA;
Jan Radecki, Ottawa, CA;
Mitel Networks Corporation, Ottawa, Ontario, CA;
Abstract
A method for detecting echo path changes in an echo canceller using the statistics of the echo canceling behavior (i.e. signal and performance information), to distinguish between new line and double talk conditions. A moving counter is incremented or decremented based on monitored levels of ERL (Echo Return Loss), ERLE (Echo Return Loss Enhancement), noise and signal energies. When the counter reaches a predetermined threshold value indicative of sustained poor echo cancellation performance, a determination is made that there is a probable new line condition (i.e. echo path change). This echo path change information is then passed to the echo canceller to enable re-convergence.