SDCCH DROPS

Hi Patrick,
If you want the MS to stay in poor coverage then increase cellreselection offset.
c2=c1 +cresoff. and then incerease the RXLEVMIN from the cell (poor coverage) to neighbor cell (good coverage). Also from the cell (good coverage)you need to adjust handover parameters in order to balance the coverage area.

Hi All,

In our network we are using Siemens equipment(BSS) And huawei switch (NSS. The problem that I am encountering is related to SDCCH drop in the borders of the contry. your support is highly needed to solve this problem

mokhtar,

it’s probably interference with neighbor country’s BTS. you can check this with drivetests or qos statistics (high rate of ho due to quality & interference)

regards,
pix

hi,

location update reject is not a sdcch drop, unless there is a problem with your NSS. You see, the location update is not acknowledged, but the radio link itself was established and released succesfully.

To clear the matter:
1/ during drivetest or with qos statistics, do you see good or poor radio conditions (call drop rate, ho quality, ho interference, AMR usage, radiolink timeout “S” counter, etc.)

if yes -> interference. Activate “SFH” 1×1, put almost all your frequency band onto those TRXs, and locate your SDCCH timeslots on “non-bcch” TRX.
Check also that your NCC (network colour code) is not the same as your neighbor country.

if no -> then it might be a signalling problem (even though it’s not logical…)

Do you have possibility to do an A-interface trace or Abis interface on those cells ? You will see if there is a problem during this signalling phase.

Regards,
pix

hi all! In our network, Nokia…
When there isa drop we check for interference, frquency,and alarms. We also check TRX quality. When TCH drop reaches to a 10+ we request field people to check branching table.Hope it helps

Plz tell me what are the major reason for SDCCH and TCH drops?

can we convert SDCCH time slots in to TCH time slots?

Mokhtar, you could get a sim card of the foreign operators and try doing a drive test to detect of there are any of them usinf the same frequency band, the frequencies used and also their penetration into you country. We had the same problem and changed frequencies, it did not work.

after doing a scan we discovered that the other operator was using the same band like us but with SFH!!!

Hi i am working with Ericsson Equipment (BSS,NSS)here we are facing high SDCCH&TCH Drop How can we reduce it.