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electron
2010-01-16, 04:41 PM
Dear Friends,


I have faced a problem in 2G network with below specification:

1.There is 900 and 1800 band (separate BCCH i mean common BCCH is not activated in the network)

2.KPI is good for deliver to costumer

3.Drive test data is not OK to make benchmark


The problem is HO from 900 to 1800 is OK bud from 1800 to 900 has problem. we have tried to adjust by layer threshold and layer hysteresis and worked on power control feature parameters but we could not to solve the problem.

Please advise .



BR///Reza

RF engineer
2010-01-16, 07:00 PM
Dear Friends,


I have faced a problem in 2G network with below specification:

1.There is 900 and 1800 band (separate BCCH i mean common BCCH is not activated in the network)

2.KPI is good for deliver to costumer

3.Drive test data is not OK to make benchmark


The problem is HO from 900 to 1800 is OK bud from 1800 to 900 has problem. we have tried to adjust by layer threshold and layer hysteresis and worked on power control feature parameters but we could not to solve the problem.

Please advise .



BR///Reza

During the drive test in system info 5ter you can see 900 frequency and NCC permit is choose as planned

gprastomo
2010-01-16, 07:12 PM
What do you mean with "1800 to 900 had problem" -> cant make HO at all or can make HO but lot of failures?

electron
2010-01-16, 08:17 PM
What do you mean with "1800 to 900 had problem" -> cant make HO at all or can make HO but lot of failures?

Thanks,There is no HO failure.The problem is hand over do not take place .Actually performance of HO between 1800 to 900 is low!

gprastomo
2010-01-16, 09:32 PM
Hi,

1. Make sure the neighbour already created properly.
2. make sure that the threshold already passed for DCS to make handover (HO DL/UL RxLevel/Qual, HO margin, Adj RxLevmin etc). For several vendor implement the layering concept that push the traffic to DCS layer. ie, the traffic will be kept on DCS as long as the RXLevel > -90 dBm (DL HO RxLevel Imperative) and usually the layer of GSM is lower than DCS so GSM is the last choice of the neighbour.
3. Make sure that Sys Info 2/5 already created on neighbour list