Hi,
in our testing 5G Standalone n78 band for SCS30 KHz and 100 MHz bandwidth used, One one single cell radiating only for testing
Get
MIB,SIB1, 5GS MM [5gNR] - Registration request,UL-CCCH [5gNR] - rrcSetupRequest are getting passed
after that getting failure message in RACH
NR5G MAC RACH Trigger CONNECTION_REQUEST
NR5G MAC RACH Attempt FAILURE_MSG2_RA_TIMER_EXP
NR5G MAC RACH Attempt FAILURE_MSG2_RAPID_MISMATCH
What will be reason?
NR5G MAC RACH Attempt FAILURE_MSG2_RA_TIMER_EXP: this is because UE is under poor RF condition;check RSRP from Log.
In case there is good coverage ,then need to check UE software issue.
Hi,
CHecked with 2 mobile phone same issue observed
cell_quality_rsrp : -86.500000
cell_quality_rsrq : -10.507813
SINr: 15 to 20
how about link adaptation ,its enable?
whats model of both mobile
what is value of Maximum number of preamble transmission
PRACH
transmit_power : -6
pathloss : 67
mtpl : 23
rach_attempt : 2
min_power : -38
i am rx prach min power -38 dbm is that OK
PRACH power = Min{mtpl, *PRACH target power * + (rach_attempt – 1) × prach Power Ramp + pathloss}
PRACH power = Min{23, *PRACH target power * + (2 – 1) × prach Power Ramp + 67}
We assume that power Ramp =1
in above case min_power : -38 ========> PRACH target power -105 dbm
in your case UE send Prach preamble with less power .
can you check configuration of PRACH target power & prach Power Ramp & Maximum number of preamble transmission
<rach-ConfigCommon>
<setup>
<rach-ConfigGeneric>
<prach-ConfigurationIndex>70</prach-ConfigurationIndex>
<msg1-FDM>
<one/>
</msg1-FDM>
<msg1-FrequencyStart>4</msg1-FrequencyStart>
<zeroCorrelationZoneConfig>7</zeroCorrelationZoneConfig>
<preambleReceivedTargetPower>-90</preambleReceivedTargetPower>
<preambleTransMax>
<n8/>
</preambleTransMax>
<powerRampingStep>
<dB6/>
</powerRampingStep>
<ra-ResponseWindow>
<sl8/>
</ra-ResponseWindow>
</rach-ConfigGeneric>
<ssb-perRACH-OccasionAndCB-PreamblesPerSSB>
<one>
<n64/>
</one>
</ssb-perRACH-OccasionAndCB-PreamblesPerSSB>
<groupBconfigured>
<ra-Msg3SizeGroupA>
<b56/>
</ra-Msg3SizeGroupA>
<messagePowerOffsetGroupB>
<dB0/>
</messagePowerOffsetGroupB>
<numberOfRA-PreamblesGroupA>48</numberOfRA-PreamblesGroupA>
</groupBconfigured>
<ra-ContentionResolutionTimer>
<sf40/>
</ra-ContentionResolutionTimer>
<prach-RootSequenceIndex>
<l139>129</l139>
</prach-RootSequenceIndex>
<msg1-SubcarrierSpacing>
<kHz30/>
</msg1-SubcarrierSpacing>
<restrictedSetConfig>
<unrestrictedSet/>
</restrictedSetConfig>
</setup>
</rach-ConfigCommon>
prach_data
resource_allocation : 4
zc_root_seq : 67
preamble_format : 5
symbol_offset : 0
numerology : 30KHZ (1)
prach_number : 0
zc_cyclic_shift : 91
3530 2021-12-14 13:23:12.059154 Qc. 5G-NR[Chipset] ______[0xB88A] NR5G MAC RACH Attempt FAILURE_MSG2_RA_TIMER_EXP
[ 2021 Dec 14 13:23:12.059154 ] [0xB88A] NR5G MAC RACH Attempt
Chipset timestamp: 2021-09-28 08:48:00.159348, CFN : 96
Dual Mode Index : 0
SIM Index : 1
Version : 131079
Major.Minor Version : 2.7
log_fields_change
log_fields_change_bmask : 0x0000
sub_id : 0
header
num_records : 1
num_attempt : 1
ssb_id : 0
csi_rs_id : 0
carrier_id : 0
rach_result : FAILURE_MSG2_RA_TIMER_EXP (1)
contention_type : CONT_DL_MCE (1)
rach_msg_bitmask : 0x01
rach_msg1 (0x01)
msg1_scs : 30KHz (3)
ul_bwp_scs : 30KHz (1)
rach_msg1
system_time
frame : 321
sub_frame : 9
slot : 1
scs_value : 1
symbol_start : 0
prach_config : 70
preamble_format : 5
preamble_format : FORMAT_A1 (5)
ra_id : 37
fdm : 0
uroot : 67
cyclic_shift_v : 91
ra_rnti : 267
rar_window_start_sfn
frame : 322
sub_frame : 2
slot : 0
scs_value : 1
rar_window_end_sfn
frame : 322
sub_frame : 6
slot : 0
scs_value : 1
backoff_duration : 0Wrong preamble detection check the clock source.
you can check the power and preambles are correct or not which UE is expecting.