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khaledkhoudi
2012-01-21, 03:14 AM
Dear experts,

I need your help in PS Call Drop problem: the vendor is Huawei . The BSC version V900R012

In one RNC, The PS call drop ratio is very high 30%, when i check the causes most of it is due to RF especialy Failure in the Radio Interface Procedure and Uplink Synchronization Failure.
Knowing that the RF condions are good (Coverage & quality) and also the problem affects all the RNC's cells, i need your help to solve this problem because customer starts to complain.

NB: we have problem in synchronization, there is no IP clock.

Best regards,

agenov
2012-01-21, 03:20 AM
this simply means that NodeB lost syncronization with the UE. If the problem is not hardware or something then check your RTWP and possible reasons in case of it is high enough.

BR
Alex


Dear experts,

I need your help in PS Call Drop problem: the vendor is Huawei . The BSC version V900R012

In one RNC, The PS call drop ratio is very high 30%, when i check the causes most of it is due to RF especialy Failure in the Radio Interface Procedure and Uplink Synchronization Failure.
Knowing that the RF condions are good (Coverage & quality) and also the problem affects all the RNC's cells, i need your help to solve this problem because customer starts to complain.

NB: we have problem in synchronization, there is no IP clock.

Best regards,

khaledkhoudi
2012-01-21, 03:32 AM
Dear agenov,

I already check the RTWP and it's normal (-100 to -106). But the drop problem is for almost all the cells that's why i suspect to be RTWP.
Can you have any other approachs i can look for ??

Thanks

agenov
2012-01-21, 04:11 PM
Have you checked in the busy hours and max value of RTWP? what is your traffic and H users during that time?
another approach is to start LMT trace at one cell that is biggest contributor and check inside the messages where you can see exact radio conditions. In my opinion if it is not third part problem like hardware and bug this is related with UL noise and more users camped on the cell... but try and check it.

BR
Alex


Dear agenov,

I already check the RTWP and it's normal (-100 to -106). But the drop problem is for almost all the cells that's why i suspect to be RTWP.
Can you have any other approachs i can look for ??

Thanks

leteo
2012-01-21, 09:51 PM
Dear experts,

I need your help in PS Call Drop problem: the vendor is Huawei . The BSC version V900R012

In one RNC, The PS call drop ratio is very high 30%, when i check the causes most of it is due to RF especialy Failure in the Radio Interface Procedure and Uplink Synchronization Failure.
Knowing that the RF condions are good (Coverage & quality) and also the problem affects all the RNC's cells, i need your help to solve this problem because customer starts to complain.

NB: we have problem in synchronization, there is no IP clock.

Best regards,

Shorten inactivity - user timer; HSDPA => DCH => FACH => Idle. But user-experience is not good.

rffreeconsult
2012-01-22, 12:52 AM
Check the location update timers to see the duration, a high rate of update that coincides with hotspot during a certain hour (busy) can overwhelm your RNC

khaledkhoudi
2012-01-23, 10:09 AM
Dear agenov,

I checked the RTWP for the most contributors cells in the BH and i found that the max RTWP is -80 and the mean is -96.
so maybe the problem is coming from external interference. what do you think??

Aljunaibi
2012-01-23, 03:50 PM
Dear Khaled, please implement PS call re-establishment feature..
It will reestablish the PS session after the drop.. which will enhance the client perception and will improve your KPI
For the time being, it seems that you have poor RSCP in this RNC

agenov
2012-01-23, 03:53 PM
RTWP is higher but in case of lot of traffic this is expected. Start RF frequency scanning from the NodeB if you have suspicion for external interference. Do a trace of such PS drop in order to get deeper in the problem...


Dear agenov,

I checked the RTWP for the most contributors cells in the BH and i found that the max RTWP is -80 and the mean is -96.
so maybe the problem is coming from external interference. what do you think??

Redrodri
2012-02-11, 05:41 AM
Dear, The value that you can serve as a reference is not the maximum, rather average. With the average value of RTWP you can see the variations or peak saccording to the time, the highest values ​​that you say no cause for alarm criticism.

We would recommend reviewing the coverage you have their cells, may do so using the propagation delay to see how much even cover. First check the coverage of the cell, also check the cell radius parameter in case of rural areas

Regards