- This topic has 29 replies, 1 voice, and was last updated 13 years, 10 months ago by bill.
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19th November 2007 at 18:31 #49747NenoGuest
dear all
first good avter noon, i need your help as i have i problem in GPRS_UL_TBF_Establishment_FailB. Regards
19th November 2007 at 21:32 #49748pixGuestit sounds like you’re working with alcatel ?
reset the cell(s), then reset the GPU, and check your GPU usage : you might need an extension of GPU’s. Check also your current NSS and BSS release, there might be some new releases that fix this kind of issues.
(FYI, gprs ul estab fail is a typical alcatel B8 problem, so don’t hesitate to raise this issue to your vendor’s interface)
21st November 2007 at 18:11 #49749NenoGuestthanks PIX
please i need more deatails about this problem, since we are using alcatel B8.
please if you dont mind i need tour email21st November 2007 at 19:37 #49750pixGuestplease, contact your TPM, he’ll guide you through this…
22nd November 2007 at 07:55 #49751NarChaiGuestHi friend
If GPRS_UL_TBF_Establishment_Fail only UL but DL is normal and most of failure come from RF and there no HW fault(TRE).
I recommend you check cell parameter “GAMMA_TNx=0” or not? if not correct them.22nd November 2007 at 21:58 #49752TNSGuestHi all,
I’m agree wiht NarChai…
If you will check the Gamma parameter, take a look to the Alpha parameter too…
Good look23rd November 2007 at 13:45 #49753NenoGuesthello NarChai
why GAMMA_TNx should be equal to zero, waht do you think about that PIX23rd November 2007 at 14:03 #49754pixGuestgamma = 0 means you disable UL PC for GPRS (note : this doesn’t disable UL PC for GSM 🙂 )
it is correct that UL PC for GPRS can have a negative impact on UL establishment sometimes (bugs in MS ? bugs in software ?). Try to put it to zero, and see if it helps.
Pix
23rd November 2007 at 15:29 #49755NenoGuestHi PIX
if we put it 20 what is that meanB.R.
23rd November 2007 at 15:52 #49756pixGuestit’s complicated, i don’t have time to explain… if you put 20, it means you have UL PC for GPRS = enable, but with a quite safe value (30 is default, but a bit aggressive)
try 0, my friend…
pix
23rd November 2007 at 16:07 #49757NenoGuestDear Pix
iam sory if i am wasting your time but realy i trust in your answers
23rd November 2007 at 17:09 #49758pixGuestyou’re not wasting my time, it’s just that I don’t have the time 🙂
i’ll just give you the formula by memory…
tx power of the next burst (i.e. timeslot) :
UL TX POWER = GAMMA – ALPHA*(DL RXLEV + 48)This is a linear equation, i’ll let you do the excel macro and try different values. If you have questions, don’t hesitate.
Pix
26th November 2007 at 04:44 #49759NarChaiGuestHi neno
How about your problem? i has problem in my network same you and i solve that i recommend you. i not sure about this parameter.
So PIX can explain you better me.I just share!
26th November 2007 at 12:20 #49760pixGuestnarchai,
have you tried turning it back on ? the same thing happened to me, ul estab = terrible for many cells. It started this way :
I enabled the PC UL GPRS. Everything worked fine for a while. Then suddenly the UL estab decreased terribly. As a troubleshooting procedure, UL PC was deactivated, and that solved the problem !
I think i re-enabled it for test trial, and it worked fine also… very weird. It might be due to some MS not supporting UL GPRS PC (??).Pix.
30th November 2007 at 09:33 #49761Yogesh singhGuestHi,
Pls try the following values of Parameters:
1.GAMMA=0,ALPHA=0,
ALPHA is sent from the BSC to the MS and decides the level of reduction of the MS output power in relation to the path loss. The values are given as a multiple of 10, i.e. the value 5 means the reduction level of 0.5.
GAMMA is sent from the BSC to the MS to give a target value for the
received signal strength at the BTS. The GPRS have no dynamic power regulation. So if the GAMMA is set to 0dB the MS will send max power when sending data on the PDCH. GAMMA =16dB gives that the MS will always send (max power – 16dB) on the PDCH. So if the GAMMA = 16dB in some area in some cells the BSC will not hear the MS when the MS have been given a PDCH to send on.
2.Check for PDCHPREEMPT:Default is 0 can be set to 2 depending on CS Traffic, so that only idle ondemand PDCHs will be preempted.
3.Put TBFULLIMIT=1,default is 2Rgds
Yogesh -
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