- This topic has 7 replies, 1 voice, and was last updated 9 years, 5 months ago by pix.
1st December 2011 at 13:47 #67562VanGGuest
in our NSN network we have problems with some Nokia models when the baseband hopping is activated..
The problems models are Nokia(1616,C1-01,C2-01 and other). The problem is with Immediate Assignment failures when try to call setup…
Sometimes the device are blocked after this assignment failure and the phone should be restarted with remove of battery . These problems is does not occurs always, for example 10 fails from 50 attempts for call establishment.
We tried to disable the hopping in tested cells and this problem does not occurs. For this I think that there is problem with this devices when the hopping is active…
Is there anybody to have idea, what can be the problem? May be some additional settings or something else?1st December 2011 at 16:13 #67563pixGuest
are you using EGSM or just PGSM in your BBH cell ?
are you using compressed inter RAT HO info ?
which HSN are you using ?
which MAIOs ?
in the immediate assign messsgae, only those few “important” info are sent… so only one of those is causing the problem.
for hopping, the cell is also sending its time synchronization info : T1, T2, T3, but it is not configureable (i think). Thanks to this sync-info, the MS is able to guess what is the hopping sequence.
pix1st December 2011 at 20:14 #67564VanGGuest
Thank you again Pix,
I will checked tommorow and give you feedback…2nd December 2011 at 12:34 #67565VanGGuest
a little additional information..
There are both E-GSM and P-GSM in BBH active cells. The strange is that there are cells with BBH activated, but there is no this problems as in the cells without hopping.
What do you think about timer T3101. Is there relation between our problem and the value of this timer. He is equal to 3sec. for all cell.
The HSN’s are from 1 to 63 and there is no MAIOs…
rrb3rd December 2011 at 08:54 #67566pixGuest
i wuold think that in some cells, there are MS which are not EGSM compatible. I’m surprised the models you are listing are not… they should be…?
Could you try to do a kind of SFH with one MA-list containing only the P-GSM band frequencies (all TRX that carry BCCH and SDCCH should be in that band) and another list with the extended frequencies only.
Then you should set a parameter called “RR ALLOCATION EGSM” (or something named like this, I can’t remember the exact name) to the value meaning that PGSM MS should be handled differently than EGSM MS.
If you try that and it works, it means indeed that the TCH failures are coming from non EGSM phones.
Also there is an indicator that counts how many phones are EGSM compatible in your network. I forgot the name, but I’m sure you’ll find it. It’s probably a cell indicator.5th December 2011 at 07:02 #67567VanGGuest
thank you for your ideas.
Wait me for feedback …
>rrb7th December 2011 at 14:15 #67568VanGGuest
step by step we tried to solve our problem but for the moment nothing:((
We find that, may be the problem occurs when the devices wants to assign the P-GSM.When E-GSM is used there is no problem with tested device??
I know that you are Alcatel master, but did you have any idea about our problem with NSN equipment?
>rrb7th December 2011 at 15:24 #67569pixGuest
i’ve no experience with NSN, but such problems are quite generic – i dont think it is specific to NSN !
i gave you pointers to isolate the PGSM / G1 problem. First of all, look for all parameters that have an influence on EGSM radio resource management. In ALU, there is such a parameter, so I’m sure there is one as well in NSN (something like “RR ALLOCATION EGSM”)