WCDMA RACH Success rate

[electron]

Hi friends,



Can any body please share RACH success rate formula in E******* WCDMA system. I also need all related counters.


How we can monitor RACH performance in cell level?


Thanks

[hari_2208]

Hope below helps!!!

from Reports

+ I dont think there is any KPI specific to RACH channels.But in genral from Technology point of view look for the below vendor specific counter /reports
+ It can be indirectly considered based on "RRC Setup Success Rate".As initial msgs are send on RACH in UL till it is moved on CELL_DCH state after RRC_con_setup msg from RNC.
+ check for counters specifc to RRC_con_setup ,RRC_CON_REQ & RRC_con_setup_com

from TEMS or Drive tool

+ check of the UE TX power if it is reaching to MAX & still you dont see the RRC Connection Setup from node-b for the RRC Connection Request send by MS....there is issue.

Use the cell specific RTWP reports & check for the RACH realted parameter for resolution/opimization.

[minhvt]

Hi friends,



Can any body please share RACH success rate formula in E******* WCDMA system. I also need all related counters.


How we can monitor RACH performance in cell level?


Thanks

I have a question same with this guide, we need a formular.

Thanks

[electron]

Hope below helps!!!

from Reports

+ I dont think there is any KPI specific to RACH channels.But in genral from Technology point of view look for the below vendor specific counter /reports
+ It can be indirectly considered based on "RRC Setup Success Rate".As initial msgs are send on RACH in UL till it is moved on CELL_DCH state after RRC_con_setup msg from RNC.
+ check for counters specifc to RRC_con_setup ,RRC_CON_REQ & RRC_con_setup_com

from TEMS or Drive tool

+ check of the UE TX power if it is reaching to MAX & still you dont see the RRC Connection Setup from node-b for the RRC Connection Request send by MS....there is issue.

Use the cell specific RTWP reports & check for the RACH realted parameter for resolution/opimization.


Thanks for your answer .



Of course there is some counter. I am exactly looking for the counters

[mon3em]

RRC Succ Rate is direct indication for RACH performance

You can get limited counters :

Percentage of RACH false detection:
pmNoPreambleFalseDetection/pmPositiveMessages

AICH negative & possitive messege
pmPositiveMessages
pmNegativeMessages

pmNoRecRandomAccSuccess

pmTransportBlocks
pmFaultyTransportBlocks

In addition to this you have to monitor also RRC Succ rate

..........................
mon3em

[hari_2208]

+ Many thanks for the post , can you pls give more details on Percentage of RACH false detection:pmNoPreambleFalseDetection/pmPositiveMessages counter.

+ I think RRC_SUCC_RATE% has below limitaion in turns of RACH success rate
CASE 1 - RRC conn req msg is only send after a preamble ( which can be send many times) till AICH is received for the same - so this creates a delta here.ie N/W wont know how many times the MS has tried preamble tx (mMAX) till it actually detects one

- Also the retry times the ms has used ( ie AICH was never received and MS again started retransmitting the preambles) as per the timer N300 ( many reason one of them is high RTWP or parameter isssues).