srsue connection to 4G network in band 46

[jmbenol]

Hello,

We are trying to connect srsue running on USRP B210 to Amarisoft eNodeB and 4G network

We succeeded in serveral bands, both FDD (band 3) and TDD (band 41, 42, etc...), but it doesn't connect when using band 46. srsue finds the cell but doesn't attach to the 4G network:

Reading configuration file ue_rf_lte.conf...

Built in RelWithDebInfo mode using 22.10.0.

Opening 1 channels in RF device=uhd with args=default
Supported RF device list: UHD file
[INFO] [UHD] linux; GNU C++ version 11.2.0; Boost_107400; UHD_4.1.0.5-3
[INFO] [LOGGING] Fastpath logging disabled at runtime.
Opening USRP channels=1, args: type=b200,master_clock_rate=23.04e6
[INFO] [UHD RF] RF UHD Generic instance constructed
[INFO] [B200] Detected Device: B210
[INFO] [B200] Operating over USB 3.
[INFO] [B200] Initialize CODEC control...
[INFO] [B200] Initialize Radio control...
[INFO] [B200] Performing register loopback test...
[INFO] [B200] Register loopback test passed
[INFO] [B200] Performing register loopback test...
[INFO] [B200] Register loopback test passed
[INFO] [B200] Asking for clock rate 23.040000 MHz...
[INFO] [B200] Actually got clock rate 23.040000 MHz.
Waiting PHY to initialize ... done!
Attaching UE...
.
...
..
.
Found Cell: Mode=TDD, PCI=7, PRB=25, Ports=1, CP=Normal, CFO=-11.3 KHz
Enabling subframe interpolation for TDD cells (recommended setting)
Enabling subframe interpolation for TDD cells (recommended setting)
Enabling subframe interpolation for TDD cells (recommended setting)
Setting TDD-config: 2, SS config: 7
Found PLMN: Id=00101, TAC=100
Random Access Transmission: seq=49, tti=1607, ra-rnti=0x8
RRC Connected
Random Access Complete. c-rnti=0x3e, ta=47
Scheduling request failed: releasing RRC connection...
Random Access Transmission: seq=34, tti=4517, ra-rnti=0x8
Random Access Complete. c-rnti=0x3e, ta=48
Scheduling request failed: releasing RRC connection...
Random Access Transmission: seq=18, tti=7397, ra-rnti=0x8
Random Access Transmission: seq=40, tti=7497, ra-rnti=0x8
Random Access Complete. c-rnti=0x3e, ta=48
Warning: Detected Radio-Link Failure
RRC IDLE 

In srsue logs we can see following error which we don't know if it could be related:

2024-03-04T17:21:30.192590 [PHY_LIB] [E] [ 4644] Returned Error while selecting PUCCH format
2024-03-04T17:21:30.192590 [PHY_LIB] [E] [ 4644] PUCCH format Format Error not supported
2024-03-04T17:21:30.192590 [PHY_LIB] [E] [ 4644] Error encoding PUCCH bits
2024-03-04T17:21:30.192591 [PHY_LIB] [E] [ 4644] Error encoding TB

I would appreciate very much if anybody could give me a hint to follow.

I attached srsue logs and enodeb/srsue configuration files

Thanks in advance and Best Regards,

srsue-band46.zip
config.zip

[jmbenol]

Hello,

As shown in srsue output, seems a problem caused by degraded radio-link

It has been mitigated by increasing tx/rx gain in both sides and, despite radio-link is still far from optimal, srsue attaches to the 4G network

Best Regads