UE not connecting to 5G network

Hello Experts,

I’m trying to solve the problem that my UE isn’t succeed to connect to 5G network.
There’s apparently a problem with Msg3 …what could be the problem for this failure?

Thanks alot for your assistance

Looks like it is not stepping up power from one preamble to another.
Make it 1 or 2dB that param.

Which parameter you meant to make?


What is the value?
MO: NRDUCellUlPcConfig
Or even better, make it 4.

Thanks, will try and update.

So you mean to put msg3-DeltaPreamble 4 dB?

Put the value 4 (8 dB).
Or try even with 3 (6dB)
What was your value?

It was 0…

Ok, this is probably the issue.

Changed it to 4, still not affected.

Is it SA or NSA?


msg3 Power = PRACH Power + (2 x msg3-DeltaPreamble), so maybe issue is PRACH power?

Where does this formula comes from?

I think the 2 factor depends on the numerology!

It looks OK.

But why I don’t see msg3?
Mean msg3 failure…

What’s the NRDUCellUlPcConfig.PreambleInitRxTargetPwr (Preamble Initial Received Target Power)

Make DeltaPreambleMsg3=6 (12 dB)
Look in OSS traces, do you see msg3 for this UE arriving at gNodeB?

I mean at cell level do you see Msg3 from other UEs?
If yes means is a UE problem;
If not means is a cell problem.

Do you have access to UE logs too? I don’t expect a 100 percent failure due to some power setting limitation. There may be an interoperability issue here.
I mean, if gnb is sending msg2, are you seeing the msg2 being decided on the UE as well? Are you sending distributed VRB to the UE which it does not respond to? I want to say that what you described as a msg3 issue, maybe a msg2 not received from JE perspective (if it is not dwcoding msg2 due to some incompatibility)

Sorry for so many questions. Just browsing :smiley:

Check content of msg 2.

What do I need to check exactly?

Check rapid if it match or not/
Could be wrong preamble detection case.

I understand what’s message 2, but what should I check there? Which parameter?