5G SA srsUE connect to commercial gNB

[yachen0409]

Hello everyone,
I'm trying to use srsUE to connect TMobile 5G network (n25 here) in US. I understand that the K and the OPc would be a problem, however, I want to collect the System Information Block(SIB) and RRC traces.

Currently, I follow the tutorial to set up 5G SA srsUE. The Hardware configuration is stated below:

• srsUE (latest)
  • Ubuntu 22.04 + i7-6700 CPU + 16GB RAM
  • UE Config
• RF Frontend
  • USRP B210 + Proxicast 8 dBi 4G/5G Omnidirectional Antenna
  • UHD driver 3.15

However, as soon as I ran the srsUE, the UE stuck at the "Attaching UE......", without further steps for 15 mins.
No messages are captured in mac, mac_nr, while only one message in nas.

In the UE log, I found that the cell selection process seems only runs once instead of keep searching, with the only info "Completed with failure."

The log can be found here with info and debug level:

• UE log (info level)
• UE log (debug level in zip)

I search in the forum and the issues, and did the following attempts already:

• Change srate (5.76/11.52/23.04mHz) and prb(25/52/106), only lowest srate here would not cause overflow message in srsUE.
• Change tx_gain (7/15/45/60/75). These number are from other discussion/issues' ue config.
• Test 5G RSRP with rooted COTS phone, the place I conducted the experiment is around -80 ~ -100dBi
  • I tried to connect to 4G LTE, and it found the cell at least.

I still cannot figure out the problem now. The last thing I though is about the CPU capability.
If anyone used 5G srsUE and successfully searched the cell/Established RRC connection. Please help me.
If not, any comments are still welcome.

[Nuradioconcepts]

srsUE is searching band n3 frequency instead of n25. I believe this is hardcoded and may be a limitation of srsUE.