Hi Experts,
My VoLTE traffic increased for an hour but user count is normal compared to other days.
RRC drops and VoLTE drops is high for this hour.
My MCS was poor during the traffic increased hour.
Is the VoLTE traffic increase in MB due to low MCS?
Sudden low MCS, for one hour only, could be due to high traffic on other cells that generate higher interference in DL, so MCS is lower in your current cell and more drops (RRC and VoLTE drops).
Assuming you are measuring VoLTE on upper layers, it shouldn’t increase because of low MCS.
You are probably seeing two different things happening in parallel.
A lower MCS means more RBs for same VoLTE call so your traffic should get into less VoLTE traffic not more VoLTE traffic.
MCS 6 for 1 hr Vs MCS 15 for 1 hr.
Which consumes more MB?
I think MCS6.
According to this it should be 15?
MCS6 consume more RBs than MCS15.
VoLTE traffic should remain the same, you are not generating more voice in the upper layers. You only should see increase if you are looking at lower layers, right?
Sorry, I don’t get your question.
MCS is as per counters for a specific hour.
If it was 6 in your case you have to focus why it suddenly decreased so much.
Yes, if enough resources VoLTE traffic should not change either with MCS6 or MCS15.
But if at limit it could go in RBs bottleneck and get into congestion.
Then you should reach a maximum and cap at it, I assume.
But that at a very extreme scenario, as QCI1 should be prioritized against others, I believe.
Maybe a step back: What do you mean by “VoLTE traffic” and where are you measuring it?
Ok, let me explain:
I had VoLTE mute call issue in a sector for 1 hr.
Upon checking VoLTE traffic in MB increased, but user count was same compared to other hours.
MCS degraded during this hour
RRC drop and VoLTE drop also increased.
Please suggest ways to investigate this issue.
Have you check radio conditions as well?
I mean ul bler, pusch sinr, etc… and dl bler in same window.
VoLTE traffic in “MB” is measured at S1? eNB PDCP?
DL bler was high.
Is measured @ eNB.
I don’t think increase in traffic impact drop, it can be UE lost.
Please check counter which increases here.
Isn’t this a clear sign of interference?
What do counters for noise says for PRBs?
No interference was there above -110.
Have you checked each PRB?
Among the 100 possible?
No, i didn’t.