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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas;color:#1F497D'>There are two common types of echo. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas;color:#1F497D'>Accoustic Echo: This is caused by microphone picking up audio from the speaker. This echo cannot generally be removed by echo cancelers. The solution to accoustic echo is to prevent the microphone from picking up audio from the speaker (or handset or earpiece).<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas;color:#1F497D'>Line Echo: This is caused by your outgoing audio “reflecting” off the far end of an analog line. This happens in all calls with a 2-wire analog portion, however in analog and digital (aka PRI) the delay in echo is so small we can’t perceive it. VoIP has far larger latencies so we can hear the echo. This type of echo MUST be canceled out before the audio is converted to VoIP.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> asterisk-users-bounces@lists.digium.com [mailto:asterisk-users-bounces@lists.digium.com] <b>On Behalf Of </b>Anurag Rana<br><b>Sent:</b> Wednesday, June 25, 2014 2:36 PM<br><b>To:</b> Asterisk Users Mailing List - Non-Commercial Discussion<br><b>Subject:</b> Re: [asterisk-users] Echo Cancellation when calling from softphone to mobile.<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif";color:black'>Is there any Software solution?<o:p></o:p></span></p></div></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><o:p> </o:p></p><div><p class=MsoNormal>On Wed, Jun 25, 2014 at 11:38 PM, Mitul Limbani <<a href="mailto:mitul@enterux.in" target="_blank">mitul@enterux.in</a>> wrote:<o:p></o:p></p><p>Put line side echo cancelation chip on ur PRI card.<o:p></o:p></p><div><div><div><p class=MsoNormal>On 25-Jun-2014 10:35 PM, "Anurag Rana" <<a href="mailto:anuragrana31189@gmail.com" target="_blank">anuragrana31189@gmail.com</a>> wrote:<o:p></o:p></p></div></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><div><div><div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif";color:black'>Hi,<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif";color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif";color:black'>I am using Twinkle to call mobile phone but there is too much noise on the mobile user's end. Mobile user's voice is echoed back to user. While on twinkle end everything is fine.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif";color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif";color:black'>Using Asterisk 11.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif";color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif";color:black'>Please suggest some way to mitigate the problem.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif";color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif";color:black'>Thanks.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif";color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Verdana","sans-serif";color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal>-- <o:p></o:p></p><div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-size:13.5pt;font-family:"Verdana","sans-serif";background:white'>Anurag Rana <br></span><span style='font-size:7.5pt;font-family:"Verdana","sans-serif";color:#38761D;background:white'><a href="http://newbie42.blogspot.in/" target="_blank">http://newbie42.blogspot.in/</a></span><span style='font-size:7.5pt;font-family:"Verdana","sans-serif";background:white'><br><span style='color:#6AA84F'>On the trampoline of life's experiences, Striving towards a saintly life in the midst of these materialistic turbulences.</span></span><o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div></div></div><p class=MsoNormal><o:p> </o:p></p></div></div><p class=MsoNormal><span class=hoenzb><span style='color:#888888'>--</span></span><span style='color:#888888'><br><span class=hoenzb>_____________________________________________________________________</span><br><span class=hoenzb>-- Bandwidth and Colocation Provided by <a href="http://www.api-digital.com" target="_blank">http://www.api-digital.com</a> --</span><br><span class=hoenzb>New to Asterisk? Join us for a live introductory webinar every Thurs:</span><br><span class=hoenzb> <a href="http://www.asterisk.org/hello" target="_blank">http://www.asterisk.org/hello</a></span><br><br><span class=hoenzb>asterisk-users mailing list</span><br><span class=hoenzb>To UNSUBSCRIBE or update options visit:</span><br><span class=hoenzb> <a href="http://lists.digium.com/mailman/listinfo/asterisk-users" target="_blank">http://lists.digium.com/mailman/listinfo/asterisk-users</a></span></span><o:p></o:p></p></blockquote></div><p class=MsoNormal><br>--<br>_____________________________________________________________________<br>-- Bandwidth and Colocation Provided by <a href="http://www.api-digital.com" target="_blank">http://www.api-digital.com</a> --<br>New to Asterisk? Join us for a live introductory webinar every Thurs:<br> <a href="http://www.asterisk.org/hello" target="_blank">http://www.asterisk.org/hello</a><br><br>asterisk-users mailing list<br>To UNSUBSCRIBE or update options visit:<br> <a href="http://lists.digium.com/mailman/listinfo/asterisk-users" target="_blank">http://lists.digium.com/mailman/listinfo/asterisk-users</a><o:p></o:p></p></div><p class=MsoNormal><br><br clear=all><o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal>-- <o:p></o:p></p><div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-size:13.5pt;font-family:"Verdana","sans-serif";background:white'>Anurag Rana <br></span><span style='font-size:7.5pt;font-family:"Verdana","sans-serif";color:#38761D;background:white'><a href="http://newbie42.blogspot.in/" target="_blank">http://newbie42.blogspot.in/</a></span><span style='font-size:7.5pt;font-family:"Verdana","sans-serif";background:white'><br><span style='color:#6AA84F'>On the trampoline of life's experiences, Striving towards a saintly life in the midst of these materialistic turbulences.</span></span><o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div></div></div></div></body></html>