General parameters to improve VoLTE MOS

What are general parameters that can improve VoLTE MOS?
If possible, for Samsung vendor.

UL quality is not so good.
And S1 issues is also there causing VoLTE issues like drops and so on.
If I improve VoLTE HO my MOS is degrading because of forbid that neighbors.

Appreciates if some one can help regarding parameter suggestion.

VoIP bundling is OFF in Huawei, but in Samsung it’s on.

Can somebody recommend as i believe in general it should be OFF.

TTI bundling is a must to be activated for VoLTE coverage improvement in Uplink.
Otherwise you need to increase your SRVCC threshold.

Thanks @RFSpecialist, TTI is enabled.
It suddenly degraded inspite other KPI same.

How about ICIC Ul and DL?
Also try to play with A3time to trigger for QCI1. Make it 100msec to avoid DL interference on cells with a low MOS.
This will also help you with the SRVCC success rate.

I need to check whether this enables or not, mostly on tdd it’s done na.
I have FDD 2600.
A3 time to trigger is 640 ms which is long delay.
As Samung setting default which is high.

OMG this is a lot.

Yes. Huawei keeps 320 ms, generally.
Does ICIC UL and DL needs to be on FDD to avoid Uplink and Downlink interference?
As normally it’s deployed in TDD.

But @RFSpecialist, TTI avoids drops but it affects mos is threshold SINR mainly I need to check enter and exit.

It depends on your SRVCC threshold.
Anyway with A3 TTT = 640msec for QCI1 you can consider this teh main reason of low MOS.

Because 640 msec for A3 event, Plus filter coefficient plus hysteresis and you are more than 2 seconds in an SINR of -3 dB or even worse.
So in locations without a dominance is a disaster to change the serving cell.
Could take as much as 4-5 seconds.
Meantime you serve on your old PCI at SINR = -5 dB or even worse.

Yes A3 high is a disaster, similarly with inter Freq A1 A2 and a5 also needs to be checked.
If they are high then this too can issue the issue.
Agreed on this, first alarms and uplink interference check then if no issue found then have to look for alternative.