CDR for 3G ???!!

[fahmi]

Hi experts,
So when analysing call drop reasons (CS services), I found that the major cause is "released RABs due to RF cause" ( VS.RAB.AbnormRel.CS.RF counter).
The potential causes for RF problems are ( coverage, missing neighboring cell configuration or interference ).
Have you any idea, if there is any other counters to correlate with to confirm one of these three problems ? :confused::confused:

thnkss :)

[electron]

Hi experts,
So when analysing call drop reasons (CS services), I found that the major cause is "released RABs due to RF cause" ( VS.RAB.AbnormRel.CS.RF counter).
The potential causes for RF problems are ( coverage, missing neighboring cell configuration or interference ).
Have you any idea, if there is any other counters to correlate with to confirm one of these three problems ? :confused::confused:

thnkss :)

You should consider to below reason also:

Drop due to UL synchronization , Drop due to SHO/IRAT/LBHO HO fail(reason Not old physical channel), Drop due to Congestion,

[fahmi]

You should consider to below reason also:

Drop due to UL synchronization , Drop due to SHO/IRAT/LBHO HO fail(reason Not old physical channel), Drop due to Congestion,

plzz, if you explain in more details the meaning of "UL synchronization" and when it happen ?

[electron]

plzz, if you explain in more details the meaning of "UL synchronization" and when it happen ?

In E******* there is such kind of reason that UE will loss its connection because of such kind of miss synchronization during connected mode and will loss its connection we can say it same as Radio Link Time out in GSM which is working based on SACCH frames and when MS does not receive this messages after RLT time connection will be dropped . Actually most affected reason is Interference and HW issue in this case

[romagdinio]

Hi,
to get the exact RF cause (i.e: if it was due to bad RSCP or Ecno or missing neighbor,....etc) you have to use Huawei's CHR tool; this tool keeps records for the last 10 RRC messages before the dropped or blocked calls. so you can see the radio conditions at which the call drop happened as well as if there was a missing neighbor.

However if you don't have this tool, you can check the missing neighbors through the counter "VS.SHO.AttASU.NCELL" which counts the number of attempts per neighbor relation, so you can check if you have a relation with high attempts and is not defined.

Best Regards,
Mohamed Magdy El-Hakim

[electron]

Hi,
to get the exact RF cause (i.e: if it was due to bad RSCP or Ecno or missing neighbor,....etc) you have to use Huawei's CHR tool; this tool keeps records for the last 10 RRC messages before the dropped or blocked calls. so you can see the radio conditions at which the call drop happened as well as if there was a missing neighbor.

However if you don't have this tool, you can check the missing neighbors through the counter "VS.SHO.AttASU.NCELL" which counts the number of attempts per neighbor relation, so you can check if you have a relation with high attempts and is not defined.

Best Regards,
Mohamed Magdy El-Hakim

Dear my friend,

Seems you are working on Huawei equipment. Would be appreciated if share some knowledge on E******* if you have experience


Thanks

[agenov]

Hi experts,
So when analysing call drop reasons (CS services), I found that the major cause is "released RABs due to RF cause" ( VS.RAB.AbnormRel.CS.RF counter).
The potential causes for RF problems are ( coverage, missing neighboring cell configuration or interference ).
Have you any idea, if there is any other counters to correlate with to confirm one of these three problems ? :confused::confused:

thnkss :)


Check SRB/TRB reset counters as well. If you have Nastar find out the top contributor and trace him, in addition you can check from there for polution, missing neighbour relations and etc.

BR
Alex

[fahmi]

so you can check if you have a relation with high attempts and is not defined.



Thank you for your reply M. Mohamed,
but what you mean by "not defined", if there is an attempt ---> the neighbour must be defined, isn't it ?

[romagdinio]

Thank you for your reply M. Mohamed,
but what you mean by "not defined", if there is an attempt ---> the neighbour must be defined, isn't it ?

Hello Fahmy,
consider the below example:

if you have 3 cells (Cell A, Cell B & Cell C). consider that Cell C is defined as a neighbor for Cell A, but is not defined as a neighbor for Cell B.
now if Cell A & Cell B are in the AS with Cell A is the best serving cell and if cell C is in the MN and is becoming good, so Cell A will attempt to add Cell C (since Cell C is defined for Cell A), however since Cell B is in the AS with Cell A the addition attempt will be considered an attempt for all cells in the AS (including Cell B which doesn't have Cell C in its neighbor list) and will be counted as an attempt between Cell B & cell C in the counter i sent you before although they are not defined.

however if in another case cell B is the best serving cell in the AS and Cell C is seen with good EcNo Cell B will not be able to add cell C and most probably the call will drop if Cell C continue enhancing.

Best Regards,
Mohamed Magdy El-Hakim

[romagdinio]

Hello Fahmy,
consider the below example:

if you have 3 cells (Cell A, Cell B & Cell C). consider that Cell C is defined as a neighbor for Cell A, but is not defined as a neighbor for Cell B.
now if Cell A & Cell B are in the AS with Cell A is the best serving cell and if cell C is in the MN and is becoming good, so Cell A will attempt to add Cell C (since Cell C is defined for Cell A), however since Cell B is in the AS with Cell A the addition attempt will be considered an attempt for all cells in the AS (including Cell B which doesn't have Cell C in its neighbor list) and will be counted as an attempt between Cell B & cell C in the counter i sent you before although they are not defined.

however if in another case cell B is the best serving cell in the AS and Cell C is seen with good EcNo Cell B will not be able to add cell C and most probably the call will drop if Cell C continue enhancing.


Best Regards,
Mohamed Magdy El-Hakim

also as "electron" said you haveto consider SHO success rate as well as the IRAT preparation and execution failures.

[romagdinio]

Dear my friend,

Seems you are working on Huawei equipment. Would be appreciated if share some knowledge on E******* if you have experience


Thanks

Hi Electron,
i am sorry, but unfortunately all my experience is in Huawei & NSN networks.

[bindi]

However if you don't have this tool, you can check the missing neighbors through the counter "VS.SHO.AttASU.NCELL" which counts the number of attempts per neighbor relation, so you can check if you have a relation with high attempts and is not defined.

Best Regards,
Mohamed Magdy El-Hakim[/QUOTE]

This counter you have mentioned, do you know which release of Huawei's RAN this is available in? As I can't see this in R12.

[fahmi]

However if you don't have this tool, you can check the missing neighbors through the counter "VS.SHO.AttASU.NCELL" which counts the number of attempts per neighbor relation, so you can check if you have a relation with high attempts and is not defined.

Best Regards,
Mohamed Magdy El-Hakim

This counter you have mentioned, do you know which release of Huawei's RAN this is available in? As I can't see this in R12.[/QUOTE]

Yes this counter is defined in RAN12

[bindi]

This counter you have mentioned, do you know which release of Huawei's RAN this is available in? As I can't see this in R12.

Yes this counter is defined in RAN12[/QUOTE]


Is it possible for you to attach one file to show this counter output? I want to see how can I get it.

[sala70vic]

Hi All,

Regarding missing neighbor in Huawei UMTS, try to enable the below switch HO_INTRA_FREQ_DETSET_INTO_ACTSET_SWITCH, description as below:

HO_INTRA_FREQ_DETSET_INTO_ACTSET_SWITCH: When the switch is on, the cells in the detected set from which the RNC receives their valid event reports can be added to the active set. The cells allowed to be added to the active set must be the neighboring cells of the cells in the active set.

regards,

[agenov]

Hi All,

Regarding missing neighbor in Huawei UMTS, try to enable the below switch HO_INTRA_FREQ_DETSET_INTO_ACTSET_SWITCH, description as below:

HO_INTRA_FREQ_DETSET_INTO_ACTSET_SWITCH: When the switch is on, the cells in the detected set from which the RNC receives their valid event reports can be added to the active set. The cells allowed to be added to the active set must be the neighboring cells of the cells in the active set.

regards,

Do you have an idea/info why these cells in the detected set must be neighbours of the other cells in the active set not anyone else? This is something i always wondering..

BR
Alex

[nieckyz]

UE will meassure all signal, some of that will be candidate for event 1a or 1b, isho or ifho target candidate and all of the meassure UE has been made are from AS since the AS are the server which served the UE, not MN.

For nokia, you can see M1014C0 for number of SHO attempt (and some other counter for ISHO and IFHO) to decide if the target cells need to define to be neighbor or not.

You can use nastar also to see same counter.