- This topic has 10 replies, 1 voice, and was last updated 9 years, 6 months ago by Wallis Dudhnath.
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28th October 2004 at 04:47 #40037vimalGuest
Can anyone help in resolving echo problem in the GSM and what may be the Probable cause of the echo in certain BTS(CITY MACRO)
29th October 2004 at 05:28 #40038OliverGuestVimal:
Normally echo in a GSM network is presented in calls to/from PSTN.
According to standard GSM Mobile Stations have the capability to reduce this efect but it depends also in which kind of mobile are you using for.
Also in transcoder unit there must be a feature or parameter called acoustic echo canceller when you set delay in miliseconds to indicated the system to cancell echo signal. Recommended value can be from 200 to 400 ms.29th October 2004 at 08:58 #40039vimalGuestThanks oliver for the reply
in my case at particular point of time the echo is coming even if both the calling and the called party are mobiles, it happen only in particular point of time. if i disconnect the call and call the same number(the MS was in the same sector)after some time i don’t hear echo.
as per u r reply if the transcoder parameter has to be changed then all the sites connected to that Transcoder has to be affected but it doesn’t happen so. what may be probable reason for that?.
can it be the Problem with particular CIC’s alone??
please reply27th May 2005 at 08:18 #40040InancGuestHi Vimal,
do you use ericsson MSC? Ericsson MSCs have Echo Cancellers. If you hear Echo from Mobile to Mobile there are ESS and ESR parameters in B-number table. You may need to modify these parameters.
As Oliver said, you can hear echo from Mobile to PSTN or from PSTN to Mobile because some PSTN exchanges are old crossbar exchanges.
27th May 2005 at 11:51 #40041InancGuestso I said wrong..It will Routing Case table..:)
29th May 2005 at 04:18 #40042vimalGuestwe are using seimens EWSD switch, my friends said that is because of problem with the CIC’s is it correct ??
24th June 2005 at 12:56 #40043Santosh Kunte , IndiaGuestWe are also facing echo related problem in PSTN to Mobile and Mobile to Mobile calls also. Can any body knows ths reason . What parameter we have to check. We are using ERICSSON AXE10 Switch.
25th July 2005 at 10:58 #40044SaikatGuestHi all experts,
Pls let me know How the Echo happens? And how it can be eliminated in NOKIA and SIEMENS based Sytems.
Thanks a lot in advance.Best regards
SAIKAT3rd March 2006 at 10:17 #40045SantyGuestLamination or handset cover also causes the Echo problem…
27th July 2015 at 06:53 #40046narasimhanGuestCan any one help to resolve the Echo issue between PSTN network to mobile network.
If a call made from A party PSTN network to B party mobile network is only hearing Echo.
In pstn network there is no option to have echo canceller.
Call connectivity: A part termination PSTN switch —-> transits switch —->B party Mobile switch.
29th July 2015 at 16:43 #40047Wallis DudhnathGuestIn the past I used to look at Echo Suppressors and Echo Cancellers (EC).
Essentially, for the PSTN you have points where the Two Wire Circuit (Local-Loop)
is connected to a Linecard (SLIC/SLAC) so that a Four wire circuit is created for
RX / TX connectivity. As a coil is used there is a chance for echoes to be generated as
the Line Circuit is “not balanced”.Using an Echo Canceller with your circuit you can inject
a signal to “dampen” the Echo. Good step is to look at your signalling routes and to configure via signalling the use of an EC.VBR/ Wallis Dudhnath
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