S1 initial context setup failure improvement

[Kamal]

Hi friends,
Need some assistance for S1 initial context setup failure improvement.
Maximum failure in ERAB_INI_SETUP_FAIL_RNL_RIP (M8006C247) counter.
Nokia system.

This measurement provides the number of failed setup attempts for initial E-RABs due to “Radio Network Layer Cause - Failure in the Radio Interface Procedure”. UPDATED: This counter is updated following the transmission of an S1AP:INITIAL CONTEXT SETUP FAILURE message sent by the eNB to the MME.

[ran_core_consultant]

Looks like issue with PRACH power and target noise level at eNodeB.

[javiersapon]

Usually cell edge UEs.

[Kamal]

Any settings which help to improve this scenario?

[mohd_mirza]

RRC guard timers values can be checked.
tHalfRrcCon.

[Kamal]

@mohd_mirza

RRC guard timers values can be checked.

It helps to improve ps drop alreday tuned to 6.

@mohd_mirza

tHalfRrcCon

Tuned to 5

[mohd_mirza]

Discrepency in Qrxlevmin also need to be checked, if any.

[Kamal]

Thanks, discrepancy is not too much high.

[javiersapon]

@Kamal

Any settings which help to improve this scenario?

In Ericsson: Some new features in L18, like UL Trigger Mobility will improve cell edge limited UEs to go another freq/rat.

[hchongpyp]

Hi Kamal, may I know what was the default value initially?

[Kamal]

For which parameter