FACH and PCH congestion

[BryxKeisha]

Dear RF Experts,

How can I check for the usage and if there is any congestion on the FACH and PCH channels? Recently, we activated the feature Cell_PCH transition and I'd like to know if there is any counter related to them. Would like to ask for your help and guidance on how to optimize these features. Thanks and waiting for your comments.

[BryxKeisha]

By the way, vendor is Huawei...Thanks!

[BryxKeisha]

Guys, come on....nobody knows? Seriously? Need you help please...

[jayk]

Can Use these formulas to check FACH and PCH Utilization

FACH Utilization - 100*{VS.CRNCIubBytesFACH.Tx/measurement duration}/ VS.CRNC.IUB.FACH.Bandwidth
PCH Utilization - 100*{VS.CRNC.IubBytesPCH.tx/measurement duration}/ VS.CRNC.IUB.PCH.Bandwidth

VS.RRC.Paging1.Loss.PCHCong.Cell shows Paging loss due to PCH congestion, so PCH congestion can be reflected.


FACH congestion is shown by these counters.
VS.FACH.DCCH.CONG.TIME - Congestion Duration of DCCHs Carried over FACHs for Cell
VS.FACH.DTCH.CONG.TIME - Congestion Duration of DTCHs Carried over FACHs for Cell

Regards, jack.

[Raiesh Khan]

Thanks i am helpfull by this formula

[hilman]

Thanks for this formula.

[RFDude_PMA]

Hi Gurus..

Do you have similar formula for E*******? W10

[Muhammad Imran Rafique]

A relevant question here, i am really confused as we have introduced URA state. After this lot of FACH involvement is there, what is the theoretical limitation of FACH. I mean how many user can be accomodated and can transmit data simultaneously. I will really appreicate if someone can share practical experience and let us know where we can find in documents. (Alex).

Do we have counters avaialble in e******* to find out the FACH utilization, congestion.

BR//
Imran

[bluewaves2008]

thank you .....I am looking for a long time.

[chefo]

I am trying to evaluate the FACH performance as well (E******* W10), but there is no such counter as in Huawei for FACH Congestion Time. However I decided to look at the relevant counters/KPIs for Channel Switching from/to Cell-FACH, as well as the average number of users in Cell Fach:

pmSumFachPsIntRabEstablish / pmSamplesFachPsIntRabEstablish

This, considered with the RRC Setup Success Rate would give an indication if we have capacity issues with the FACH.

I have posted the KPI formulas here: http://www.finetopix.com/showthread.php?31133

[plannerguy]

Hi

Is there anu thing similar in NSN. also how would we optimize FACH and PCH congestion.

Regards
Plannerguy

[jayk]

Hola Friends, I got these formulas from Huawei RAN14 document. But I have doubts, requests to experts to explain few question?

-PCH usage = VS.UTRAN.AttPaging1/(<SP> x 60 x 5/0.01)

-Usage of an FACH carried on a non-standard SCCPCH = VS.CRNCIubBytesFACH.Tx x 8/[(60 x <SP> x 168 x 1/0.01) x VS.PCH.Bandwidth.UsageRate x 6/7 + [60 x <SP> x 360 x 1/0.01) x (1- VS.PCH.Bandwidth.UsageRate x 6/7)]

-Usage of an FACH carried on a standard SCCPCH = VS.CRNCIubBytesFACH.Tx x 8/(60 x <SP> x 360 x 1/0.01)
SP indicates the measurement period in seconds.

i) In the PCH Formula, why 60*5 is used in denominator?
ii) I could not understand second formula too, 167?, 6/7?
iii) In third formula, 360 is used in denominator? Why 360?

If someone understand the formula, please explain.

[sobatkufatah]

For reducing PCH congestion significantly, Usually I changed parameter PagingSendingTimes from 3 to 1. But it is for ZTE equipment. For Huawei, as I know it is hard coded.

[jenriqp]

Hi !
You can see the following counters:
VS.CellFACHUEs
VS.CellDCHUEs VS.CellPCHUEs

these counters show users number in every channel



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