QCI1 Access issue in one site (QCI5 and QCI9 are fine)

Hi Experts.
I have QCI1 access issue in one site (but QCI5 and QCI9 are fine).
What can be the reason?
Strange strategy of customer is intra freq reselection not allowed but for all sites.
And only this site affected.
No alarm found.

No GBR resources available.

But Retainibility is fine, QCI1, how come?

Check number of VoLTE users.
Check also SRS and PUCCH resources.
Check also handover failures due to same reason: no resources in target cell.

OK, but LTE and remaining things fine.
No utilization as such 18 percent.
VoLTE users I need to check…

If number of VoLTE users is a flat line in counters across hours then you have an issue of no resources available for GBR.

For VoLTE muting will DL VOIP bundling switch off help as erlang increase?
Apart from interference and poor coverage no physical.

Parameters wise
Any parameters you can suggest. (Vendor is Samsung)
For VoLTE muting.



I can suggest one: A3 timeto trigger for intrrafreq and interfreq events to 100 or 160msec.
Then you will fix all mute calls due ot dl interference.
You still have to mitigate those due to UL poor coverage.

For inter it’s a1, a2, a5 with common group I’d gbr and non gbr.
This can solve issue.
Ofa3 inter.
Few sites are only affected so I will suggest to do some site trial.

What do you mean by intra freq reselection is not allowed?
For VoLTE access issue, at what stage you are facing issue?
RRC setup or eRAB setup?
Initial attempt or incoming handover?
You can try enabling Preemption feature to accomodate more VoLTE users, if capacity is exausted by non VoLTE users.

eRAB qci1 stage issue.

Some factors required in QCI1 E-RAB setup but not required in QCI5/9 setup:

  • insufficient downlink/uplink transport resources
  • no radio resource
  • security mode failure
  • conflict with X2 procedure