srsUE/bladeRF Difficulty Syncing with Real eNodeB

[sonium-labs]

Issue Description

Seem to be unable to sync to SFN with bladeRF micro 2.0 xA5.

Setup Details

• Install bladeRF native drivers and srsRAN 21.10
• Connect bladeRF via USB3.0
• Run srsUE

Expected Behavior

Find cell, sync SFN, begin cell camping process.

Actual Behaviour

Finds cell/decodes MIB, fails to sync to SFN (via logs), endless idle state in sync.cc state machine.

Steps to reproduce the problem

Including my ue.conf and two logs.

Additional Information

SNR is barely sufficient to acquire MIB it seems but eventually srsUE is able to decode it (also tried different antennas, decreasing proximity to tower and powering with the 5V adapter to no avail). Have tried both 'auto' and '27' (as is recommended for bladeRF) values for the time_adv_nsamples, and found the same results as above (no SFN lock).

[sonium-labs]

Hello all,

Have spent some more time on debugging this, and have some additional insight to share.

I was able to test closer to the real eNB, and was able to greatly improve my received SNR, and it seems srsUE is effectively able to sync with SFN and the general signal (logs show "in sync"). I also realized I had never set my desired PLMN, so I did that as well. At the moment I am not using a SIM card, so I instead manually edited the IMSI in ue.conf to specify the home PLMN. I am not transmitting at the moment without a legitimate SIM. However, it appears now that I fail to acquire SIB1 and subsequently the PLMN of the found cell. Posting some logs here.

What could cause this? If anyone has any insight to share, I would love to hear it--thanks for your time!

[antonioalbanesedev]

Hey @sonium-labs, did you make any progress here?

I am trying the same thing but I get stuck at Found Cell. No attempt to actually attach.