- This topic has 30 replies, 1 voice, and was last updated 6 years, 8 months ago by Gailan Bakr.
29th April 2008 at 16:34 #52215dkumarGuest
We are using ericsson equips and in a few sites we have ICM band to be 5.And we are facing a lot of call drops.Whats the cause and how can it be solved29th April 2008 at 19:04 #52216pixGuest
is ICM related to interference measurements during idle mode ?
in this case, it shows a lot of interference in the UL direction, or possibly some hardware problems that generated noises in the system (TRX issues ?).
You could check your frequency planning, perhaps activate frequency hopping and UL power control.1st May 2008 at 15:35 #52217dkumarGuest
Well we are using frequency hopping.And we have changed the whole RBS.So it cant be a hardware issue.And also the frequency.We have changed it too. Please explain on UL power control and how it could resolve this issue1st May 2008 at 19:44 #52218pixGuest
i’m afraid your issue requires someone that knows about ericsson.. i’m not sure i understand what is ICM 🙂
anyway, if your qos looks like there is a lot of interference, and there is no interference from your own network, and there is no hardware faults, then i would suggest you are facinf an external interferer (other operators, other technologies, alarm system, army radar, anti-theft systems, etc etc etc)
you could perform some frequency scanning in the area, while turning your site off for a while.
it could also be your antenna, or feeders, but that’s quite a rare problem.15th May 2008 at 06:14 #52219SugunGuest
May be try switch off the repeaters/Boosters installed within 1Km radius one by one and then check ICM23rd May 2008 at 16:45 #52220RichardGuest
ICM implies Idle Channel Measurements and this indicates the signal strength measurements on idle channels. This is used to at assignment to allocate the best channel, that is channels with very low noise (ICM 1)
With ICM of 5 corresponding to high drops in the UL, it implies high interference and you need to check your frequency plan, overshooting cells, hardware faults, etc23rd May 2008 at 19:54 #52221ArpanGuest
chk for any booster in that area.. may be that is misbehaving… and causing interference in the uplink18th June 2008 at 08:51 #52222emile allongoGuest
Can you help me how i can check icmband problem with log file after drive test?
BR21st June 2008 at 01:34 #52223SbhattaraiGuest
for high ICMBAND in ericsson system, more likely the issue is related with the hardware, radios.do you have TMAs? or RXAIT system to get more receive line to share between GSM and UMTS? some of these high ICMBAND has been fixed with simply frequency retune, some of them with bad TMAs replacement as well as some time with alarms on the RXAIT. ICMBAND got clear after we reset the RXAIT.some of the worst icmband we noticed in GSM site where we are sharing the line with UMTS where after doing lots of cable check,sweeep test,radio replacement…no luck and finally the repeater nearby area was causing and after we turn off the repeater and measured everything was good and icmband level was 1.Please try one thing at a time.Good Luck.30th June 2008 at 09:40 #52224SHINIGuest
high ICM band can be caused by external interference.you cant see this from TEMS log files as the log files shows downlink data.
The best way is get a spectrum analyser and try to check on this. Let me know if this is an inbuilding site17th March 2009 at 19:09 #52225x1carrierGuest
Does anyone have any installation procedures or documentation on RX-AIT frame installations?18th March 2009 at 05:57 #52226AliAsgherGuest
Band 5 Interference is too high. If your LIMIT4 is the default value then it corresponds to an interference level of better than -88dB.
Best way is to check the nearby sites for interference too. [Probably it is external interference due to Jammers or Military transmitters]. See if you can pinpoint a possible location using Interference in the area.
But Spectrum Analyzer is the best solution. Coupled with a directional antenna, you can dig out the source of interference. [Do remember to hunt for interference in the hours when ICM band 5 is visible in stats]23rd December 2009 at 12:56 #52227noorul ameenGuest
please explain ICM band value concept in Ericsson BTS and how to reduce ICM band value in ericssion BTS.15th June 2010 at 05:38 #52228MoojahidGuest
I wanna know the ICM Band details 1 to 5. Is it only escalate interference?15th December 2010 at 06:35 #52229Munish MankotiaGuest
WE ARE FACING HIGH ICM BAND PROBLEM AT INTER BSC LOCATION ALSO ON BOTH SITES TRIBAND ANTENNA’S ARE INSTALLED AND ARE SITES ARE NEWLY ON-AIR UMTS SITES .