Hi Deepak,
(1) There is no rule in echo cancellation to use two echo cancellers.
(2) Some authors suggest to use additional filters or best converged filter
coefficest set
to give better echo cancellation in case of echo path variations orin case
ofdoble talk. Some authors call this additional filters as "Auxiliary
filters". It may use same algorithm as the primary echo canceller or a
simplified one. Your logic should automatically turn on/off of the
primary/auxiliary echo canellers depend on the situation. For reference please
refer: "Siho Kim, KennsungBae, 2002 IEEE paper .... Title: "Applying an
auxiliary fitler in ....".
Regards,
Sameer
--- On Tue, 4/21/09, Deepak Garise wrote:
From: Deepak Garise
Subject: [echocancel] Redundant or 2nd echo canceler in Line Echo
Cancellation
To: e...
Date: Tuesday, April 21, 2009, 11:56 PM
Hi,
I would like to know if it is normal to include a 2nd redundant echo canceler
algorithm for line echo cancellation.
I came across brief notes on the internet that suggested use of two echo
cancelers in line echo cancellation. The additional echo canceler is enabled in
case the primary echo canceler goes out of bounds (diverges). I could not find
much useful information on this subject.
1. Is this a general rule in LEC (including 2 cancelers)?
2. What kind of algorithms are preferred or generally used in the 2nd redundant
echo canceler?
Any pointers would be of great help. Thanks.
Regards,
Deepak
_____________________________________