Help for HSDPA service drops.

[kadir]

Hi all;

I have problem about HSDPA, in our network, when the users is connected to internet, if they dont download anythink, the modem disconnects and this happens at busyhour.What are the possible reasons?

Secondly, our RAB establishment failure rate is high, does it effect the drop rate or not ? This also happens in busy hour at high loaded node-b.

could you show me the way at least, please help...??

BR.

[kadir]

no comment ?

[wolverine]

Hi Kadir,

When you say "the modem disconnects", do you mean a PDP Context Deactivation?

If you are talking about the RRC connection being released, then quite a few devices (esp. smartphones) will send a Signalling Connection Release Indication when there is no activity for 5-10s. This is termed "Fast Dormancy", and your counters should take this into account and not count it as an abnormal release.

If neither of the above is helpful, then it might help if you provide some further information about your problem.

[cococrunch]

Hi Kadir,

RAB Estab failures are likely to occur on high loaded NodeBs. May I ask which capacity is congested, i.e. CE, Iub, Codes, UL/DL Power, etc.?? And what is the failure cause of the RAB Estab?

If you look at the trend per hour of a CONGESTED site with high RAB Estab fails, you will notice that failures occur on the busy hours only (6:00PM - 8:00PM in our network). This is one quick sign to look at congested sites.

Thanks.

[kadir]

Hi friend;

when i look at the stats, Our congestion is on UL CE. can i ask, how many CE is used on HSPA service per user? or is it needed for HSPA? in our licence the CE elements are max. in UL/DL. If it is because of the congestion i think we need new Node-B, whitout this we can not solve this problem.

Thank you, so much.

Hi Kadir,

RAB Estab failures are likely to occur on high loaded NodeBs. May I ask which capacity is congested, i.e. CE, Iub, Codes, UL/DL Power, etc.?? And what is the failure cause of the RAB Estab?

If you look at the trend per hour of a CONGESTED site with high RAB Estab fails, you will notice that failures occur on the busy hours only (6:00PM - 8:00PM in our network). This is one quick sign to look at congested sites.

Thanks.

[cococrunch]

Hi Kadir,

CE usage is shared in HSPA depending on Baseband dimensioning. In NSN, CE requirement are as follows.

1. 16 users per BTS --> 32 CE required
2. 16 users per cell --> 96 CE required
3. 48 users per BTS --> 80 CE required
4. 48 users per cell --> 240 CE required


This is only for HSPA downlink, associated HSDPA UL and HSUPA are not included. HSUPA is not enabled in our network yet because of heavy CE usage(more often than not UL CE util is greater than DL CE Util). I think its better to have RU10(FSME) first before enabling HSUPA.

If not RU10, you can try to activate the feature HSDPA 16 kbps UL Return Channel. This enables you to have 1 CE(16 kbps) usage on the associated HSDPA UL rather than 4 CE(64 kbps), that is 75% off on the associated HSDPA UL CE usage.

Thanks

[maasricht]

Hi Kadir,

CE usage is shared in HSPA depending on Baseband dimensioning. In NSN, CE requirement are as follows.

1. 16 users per BTS --> 32 CE required
2. 16 users per cell --> 96 CE required
3. 48 users per BTS --> 80 CE required
4. 48 users per cell --> 240 CE required


This is only for HSPA downlink, associated HSDPA UL and HSUPA are not included. HSUPA is not enabled in our network yet because of heavy CE usage(more often than not UL CE util is greater than DL CE Util). I think its better to have RU10(FSME) first before enabling HSUPA.

If not RU10, you can try to activate the feature HSDPA 16 kbps UL Return Channel. This enables you to have 1 CE(16 kbps) usage on the associated HSDPA UL rather than 4 CE(64 kbps), that is 75% off on the associated HSDPA UL CE usage.

Thanks

I want to mention CE for Flexi Rel2 on RU10.


1. 16 users per BTS --> 32 CE required
2. 16 users per cell --> 96 CE required (3 cells)
3. 48 users per BTS --> 72 CE required
4. 48 users / 64 users per cell --> 216 CE required

If use FSMD/ FSME, no needed to reserve CE for CCCH.

[mirza]

Hi all;

I have problem about HSDPA, in our network, when the users is connected to internet, if they dont download anythink, the modem disconnects and this happens at busyhour.What are the possible reasons?

Secondly, our RAB establishment failure rate is high, does it effect the drop rate or not ? This also happens in busy hour at high loaded node-b.

could you show me the way at least, please help...??

BR.

Hi

can you tell me if possibel , you work for which carrier / network ?

thanks

mirza

[gprastomo]

Hi all;

I have problem about HSDPA, in our network, when the users is connected to internet, if they dont download anythink, the modem disconnects and this happens at busyhour.What are the possible reasons?

Secondly, our RAB establishment failure rate is high, does it effect the drop rate or not ? This also happens in busy hour at high loaded node-b.

could you show me the way at least, please help...??

BR.

Hi,

FIrst of all, the PDP context deactivation could be caused by several reason :
1. if there is no activity for some period, the RRC state will move to FACH then CELL PCH then idle mode (disconnect), this one is methode to make the Radio Resource more efficient, usually it takes ~1 hour depend on your parameter setting, check this behaviour
2. according to your information, the RAB estab fail is so high, this one of indication,let say users try to make a call then fail so they will try to make a call again more than 1 in the same time so the Radio Load both UL&DL will overloaded (imagine 100 users try to make call in the same time) and the RACH power is higher than dedicated channel so the possibility of having overload on the radio side is so high, during this time the existing user which already connect to the network will be affected then by Radio REsource procedure the existing call will be downgraded even will be dropped (include HSDPA), then the new Call will be rejected. So try to investigate why the Rab Estab fail is so high, is it due to UL/DL Admission control, IuB Blocking, CE blocking, IuPS/CS blocking see on the stats then try to solve it.

3. You have to breakdown on the counter which on of the most drop on that particular cell, is it due to radio, capacity etc ?

try above first the we can see on the next step

regard

[kadir]

Hi

can you tell me if possibel , you work for which carrier / network ?

thanks

mirza

hi,

i work for huawei wcdma network

thanks