UE is able to decode MIB and SIB but UE is not initiating RACH request

Equivalent to 7D1S2U.

Check TDD DL UL configuration at the end in SIB1.

Here is the SIB1 message:

Yes, it’s DDDSUUDDDD.

Please, can you highlight on picture, where it is mentioned?

From pattern-1, you can get information about the starting slot, as highlighted. Here, we have 3 continuous downlink slots, followed by the number of symbols indicating a special slot. In this case, the first 6 symbols are for DL, the last 4 symbols are for UL, and the 4 symbols adjacent to the downlink symbols are for switching in the special slot. The next 2 slots are for UL.

Moving to pattern-2, you can see there are 4 consecutive slots for DL. By combining pattern-1 and pattern-2, you get a pattern like DDDSUUDDDD.

5G NR TDD Slot Configuration :point_down:

Check here, they have explained very well.

DDDSUUDDDD, right?

Better if you could provide qxdm log with default dmc, or provide min,sib & sib2 info

Have you modified or replaced RU?
Is it lab environment?
Then might be your Xran parameters are culprit you need to check prach iq width

Could it be due to Cell Barred issue?

Hi Experts.

I am still facing RACH initiation issue.

I’m curious about the NR5G RRC Blacklist update message.

Can anyone explain what it involves?

used to update the blacklist of forbidden cells or frequencies in a UE

Used to update the blacklist of forbidden cells or frequencies in a UE.

Live or Lab?

Thanks.

Lab network.

What is the PLM used?

Latest Update:

We observed that when our gNB PLMN is changed to MCC 001 and MNC 01, the UE initiates a RACH request. It appears that Indian-manufactured Samsung S23 devices are not initiating RACH towards PLMN 302 992.

1 Like

I think 302 992 is not a valid plmn from 3gpp defined list. (https://www.mcc-mnc.com/)
Andriod has plmn list updated, this could be one reason of blacklisting cell from UE RRC.
Better to test always with 001 01 plmn which 3gpp offical test plmn.

1 Like

Hi

I have faced a problem that looks like the one you have, in a LTE Private Network.
One thing that happened is that the CPEs used to connect successfully, but cellphones did not. The phones read SIB msgs but there was no RACH.
To solve the problem we applied “Combined Attach” and enabled a set of QCIs at CORE. There was no voice service enabled, so phones asked for a set of QCIs that were not in SIB/MIB, so it ignored network and did not send RACH.
We had a long fight to find the solution. CORE and BTS manufacturer debbuging the logs.

I hope it helps.

Thank you @Glaucoligg

I will try to check internally with team and work on it