5G RACH attempts fail in drive test

5G NR
,
1

Hi,

5G standalone network with single cell only radiating for testing purpose n78 band ,30 KHz SCS and 100 MHz bandwidth, getting RACH attempt failure Ue not able to connect the gNB

16:55:15.453 17:27:27.790 <--- BCCH:BCH 5GNR 5GNR MasterInformationBlock
16:55:15.453 17:27:27.840 <--- BCCH:DL SCH vF90 5GNR systemInformationBlockType1 - MCC : 1(3GPP Test) / MNC : 1(3GPP Test)
16:55:15.635 17:27:27.874 ---> UL 5GMM vF40 5GNR Registration request
16:55:15.793 17:27:27.879 ---> UL CCCH vF90 5GNR rrcSetupRequest
16:55:15.793 17:27:27.879 5GNR RACH 5GNR 5GNR MAC RACH Trigger - CONNECTION_REQUEST
16:55:15.794 17:27:27.962 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG2_RAPID_MISSMATCH
16:55:15.795 17:27:28.025 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:15.797 17:27:28.085 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:15.798 17:27:28.145 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:15.799 17:27:28.205 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:15.844 17:27:28.265 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:15.846 17:27:28.325 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:15.847 17:27:28.342 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG2_RA_TIMER_EXP
16:55:15.964 17:27:28.362 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG2_RA_TIMER_EXP
16:55:15.966 17:27:28.425 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:16.075 17:27:28.485 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:16.080 17:27:28.545 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:16.185 17:27:28.562 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG2_RA_TIMER_EXP
16:55:16.185 17:27:28.582 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG2_RA_TIMER_EXP
16:55:16.185 17:27:28.602 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG2_RA_TIMER_EXP
16:55:16.187 17:27:28.665 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:16.303 17:27:28.725 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:16.303 17:27:28.742 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG2_RA_TIMER_EXP
16:55:16.360 17:27:28.805 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:16.361 17:27:28.865 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:16.470 17:27:28.882 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG2_RA_TIMER_EXP
16:55:16.471 17:27:28.902 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG2_RA_TIMER_EXP
16:55:16.472 17:27:28.965 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:16.589 17:27:29.025 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:16.708 17:27:29.085 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:16.710 17:27:29.145 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:16.807 17:27:29.205 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:16.808 17:27:29.265 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:16.925 17:27:29.325 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:16.926 17:27:29.385 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:17.033 17:27:29.445 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:17.146 17:27:29.505 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:17.148 17:27:29.565 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:17.205 17:27:29.625 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:17.312 17:27:29.685 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:17.322 17:27:29.745 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:17.324 17:27:29.805 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:17.912 17:27:29.865 5GNR RACH 5GNR 5GNR MAC RACH Attempt - FAILURE_MSG4_CT_RESOLUTION_EXPIRED
16:55:17.912 17:27:29.879 5GNR RACH 5GNR 5GNR MAC RACH Attempt - ABORTED
16:55:17.913 17:27:29.909 <--- BCCH:BCH 5GNR 5GNR MasterInformationBlock
2

NR addition is failing due to RACH failure (MSG2 Failure)----check LA adaptation is ebable

Possible Root Cause:

  • The accessed 5G cell is not the strongest cell or the inter-cell interference is severe.
  • The PRACH parameter is incorrectly configured or the access fails due to physical layer reasons.
3

Hi,

In our live wireless network testing with gNB

we are doing 2 type of testing

one with With XCAL drive test tool and other With Ue emulator

With XCAL drive test tool ( with mobile phone ) we are getting RACH failure , but with Ue emulator we are able to capture all the message from gNB what will be issue

In Ue emulator upto PDU session PDU Session Establishment Accept message can be captured

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