3G NOKIA (RRC and CS HSDPA fails)

[indrarui_costa]

dear all,

I have problem with my network 3G NOKIA..

1. what the solution if any case setup HSDPA fails due to UL dch fails?
2. and RRC setup fails due to AC or radio?

need you help,

many thanks

[gprastomo]

1. UL DCH Fail -> maybe you have congestion on the HSDPA UL Return channel, since in Nokia RNC has fixed 64 kbps return channel and you can activate 16 kbps UL return channel by feature which have good impact on CE & Power utilization. If you have enough CE you can increase number of CE
2. Reject due to AC-> you need to specify whether it s DL or UL, then you need to check your coverage maybe it has overshooting cell or may be just a power spike then you can increase the AC threshold.

br

[indrarui_costa]

Thanks for you respone gprastomo,

The CE no conjestion, and what parameter can change to reduce setup HSDPA fail UL DCH ?

Sorry , i'm still junior

many thanks,

[jan74]

Thanks for you respone gprastomo,

The CE no conjestion, and what parameter can change to reduce setup HSDPA fail UL DCH ?

Sorry , i'm still junior

many thanks,

Can you please tell me what exact counter is being triggered for your UL DCH Fails?

If you have AC failures for the RRC, there are several possibilities. I have found that it tends to go nuts when the PTx is too high as opposed to the PRx being too high.

[wackymyke]

To your question: what parameter can change to reduce setup HSDPA fail UL DCH ? This a RNC parameter called HSDPA16KBPSReturnChannel to set 16kbps UL return channels and helps improve UL dch failures

[b20ruo]

Need some help to with HSDPA fail UL DCH.
I have this fails on cell with HSUPA enabled and also not enabled, no CE congestion, 16kbpsUL return channel is enabled.
For cell with HSUPA, we tried to deactivate HSUPA, and this fails were less but fails due to BTS, CE congestions were increased and yet, with HSUPA disabled, there were more CE used than with HSUPA activated. Strange.
Any help from experts? Please

[jan74]

Please clarify what exact failure you get? Is your HSDPA failing because there is no UL Return Channel possible?

[melkaiy]

dude this has something to do with admission control. please check your configuration regarding what DCH channels/capacity has been set up in your network.

First, clarify which configuration in the capacity then check the hsdpa no of user limit.

Second, check the Prx_Target_BTS threshold and Prx_Target_offset threshold in the admission control parameters. The network is already at overload mode that's why you keep on receiving rejects in the admission. You can increase the Prx_Target_BTS and the Prx_Target_offset threshold at acceptable value.

Please add reps if this one helps. thanks :)

[paboya]

So the summary
How to decrease the UL DCH Fail

1. Check PRACH Delay time, if the range is wider than expectation, do downtilt
2. If HSUPA enabel, try to disable
3. Cek Returun Channel, parameter : CheckHSDPAxxKBPSReturn Channel
4. Check PRX_Target_BTS

Any correction

[b20ruo]

what value is good for PRX_target_BTS?

[foxito1]

Hi b20ruo,

You can try prxtarget = 30, with this value the admission control will be disabled, so RT traffic can use the whole available power for uplink. It could affect HSDPA traffic.