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usama0795
2011-10-26, 04:22 AM
Can anyone highlight the cause of high interference on idle TCH in EGSM Band as constant interfernce is obserevd in EGSM desginated frequencies....as presence of some external source is obvious but can anyone share if EGSM band is interfered.....city KPIs were improved by configuring DCS as outer zone but can anyone share some material on it. OR some other ways to reduce the effect of interference except for pushing traffic to DCS band.....

tremalnike
2011-10-26, 05:13 AM
Hi friend,
you need to find reason for this interference. There is no prescription or material.
Some old flight radars cause interference in E-Band. Also if you use shared antenna systems (Two operators use same AFS , GSM&U900 at same AFS) some inter-modulation problems may appear.
First, just start to investigate - lock cells in affected area and perform Spectrum analyze (in the night if this problem existing).

Also share more info - is the interference is permanent ? If not - when appear ? And etc.

white_Noise
2011-10-26, 06:51 AM
Can anyone highlight the cause of high interference on idle TCH in EGSM Band as constant interfernce is obserevd in EGSM desginated frequencies....as presence of some external source is obvious but can anyone share if EGSM band is interfered.....city KPIs were improved by configuring DCS as outer zone but can anyone share some material on it. OR some other ways to reduce the effect of interference except for pushing traffic to DCS band.....

Actually it depends on the cities, from my experience ,If your living in an Islamic countries, you'll be facing a lot of Mousque Jamming sources, these sources might be constant, or appearing as spikes on prayer times, you can monitor the IOI stats to determine determine what source of jamming you might have.

srilasitha
2011-10-26, 07:02 PM
CDMA is possible cause for interference.

this is common when a CDMA operator which having DL frequency near to UL EGSM band

usama0795
2011-10-26, 10:13 PM
Continous interfernce is observed on EGSM TCH Band I mean there couldne be that many jammers and no CDMA deployed here have done spectrum analysis but couldnt determine the source Uplink band is permanently raised in Spectrum Analyzer....kindly see the GRAPH....

justdream
2012-03-16, 12:46 AM
Dear Experts, please share your exp.
as I face the same situtation in my country/ network..

fahmi
2012-03-31, 05:58 AM
Hi all,
As srilasitha (http://www.finetopix.com/member.php?21361-srilasitha) said, it seems that the cohabitation of UMTS 900 and EGSM causes interference in both systems, and for example, for U900 cell we notice a higher RTWP (up to -60 dBm) so, if it is the case, try to lock one cell (EGSM or U900) to confirm its effect on the other one.

BR,
Fahmi.