No cell synchronization found, abandoning

Projects RAN Forum
1

Hi everyone,

For my project I have to run enb on USRP b210 and UE on LimeSDR board. I can successfully run enb with following command in TDD mode on USRP b210:

sudo -E ./lte-softmodem -O …/…/…/ci-scripts/conf_files/enb.band40.tm1.25PRB.fairScheduler.usrpb210.conf -d --nokrnmod 0 --noS1

and after that I run UE by a LimeSDR board on another computer with following command

sudo -E ./lte-uesoftmodem --rf-config-file …/…/…/targets/ARCH/LMSSDR/LimeSDR_above_1p8GHz.ini -C 2350000000 -r 25 --noS1 --nokrnmod 0 --ue-txgain 20 --ue-rxgain 50 --ue-scan-carrier

But unfortunately, UE doesn’t connect to enb and after prints some outputs that were brought as follow, it prints "No cell synchronization found, abandoning"

[PHY] Not yet implemented: noise power calculation when prefix length == EXTENDED
[PHY] [UE0] Initial sync : Estimated power: 30 dB
[PHY] [initial_sync] trying carrier off 7500 Hz, rxgain 0 (DL 2350007500, UL 2350007500)
[LMS] rx frequency:2350.007500;
cal 0: freq 3500000000.000000, offset 44.000000, diff 1149992500.000000
cal 1: freq 2660000000.000000, offset 55.000000, diff 309992500.000000
cal 2: freq 2300000000.000000, offset 54.000000, diff 50007500.000000
cal 3: freq 1880000000.000000, offset 54.000000, diff 470007500.000000
cal 4: freq 816000000.000000, offset 79.000000, diff 1534007500.000000
[PHY] [UE thread Synch] Running Initial Synch (mode 0)
[PHY] Initializing frame parms for N_RB_DL 25, Ncp 0, osf 1
[PHY] lte_parms.c: Setting N_RB_DL to 25, ofdm_symbol_size 512
[PHY] [UE] lte_sync_time: Sync source = 1, Peak found at pos 30144, val = 213756 (26 dB)
[PHY] Initializing frame parms for N_RB_DL 25, Ncp 0, osf 1
[PHY] lte_parms.c: Setting N_RB_DL to 25, ofdm_symbol_size 512
[PHY] Initializing frame parms for N_RB_DL 25, Ncp 1, osf 1
[PHY] lte_parms.c: Setting N_RB_DL to 25, ofdm_symbol_size 512
[PHY] Initializing frame parms for N_RB_DL 25, Ncp 1, osf 1
[PHY] lte_parms.c: Setting N_RB_DL to 25, ofdm_symbol_size 512
[PHY] Not yet implemented: noise power calculation when prefix length == EXTENDED
[PHY] Not yet implemented: noise power calculation when prefix length == EXTENDED
[PHY] FeMBMS CAS Extended prefix: CellId 148 metric 26, phase 4, flip 1, pbch -1
[PHY] Initializing frame parms for N_RB_DL 25, Ncp 0, osf 1
[PHY] lte_parms.c: Setting N_RB_DL to 25, ofdm_symbol_size 512
[PHY] Initializing frame parms for N_RB_DL 25, Ncp 0, osf 1
[PHY] lte_parms.c: Setting N_RB_DL to 25, ofdm_symbol_size 512
[PHY] Initializing frame parms for N_RB_DL 25, Ncp 1, osf 1
[PHY] lte_parms.c: Setting N_RB_DL to 25, ofdm_symbol_size 512
[PHY] Initializing frame parms for N_RB_DL 25, Ncp 1, osf 1
[PHY] lte_parms.c: Setting N_RB_DL to 25, ofdm_symbol_size 512
[PHY] Not yet implemented: noise power calculation when prefix length == EXTENDED
[PHY] [UE0] Initial sync : Estimated power: 30 dB
[PHY] [initial_sync] No cell synchronization found, abandoning
[PHY] Dummping Frame … bye bye
libusb: warning [libusb_exit] application left some devices open

If someone knows how to fix this problem, please let me know.

thanks in advance,
Kumo

2

Saying what software you’re using might be a good start :slight_smile:

3

Dear Andrew,

I’m sorry, I forgot to talk about the software using. I’m using Openairinterface v1.1.0 for setting up my LTE. In this set up, I have used a LimeSDR as a UE and a USRP b210 as eNB.

If any other information requires to clear the problem, please let me know.

Thanks a lot,
Kumo

4

Thanks.

I’m afraid I don’t know of anyone who has recently used OAI with LimeSDR and could not say what the current status is for hardware support. You’d probably be best asking in the OAI community.

I suspect you will have more luck with srsRAN (previously known as srsLTE).

5

Thank you Andrew for responding. Definitely you right. It is better to ask the OAI community about the problem.

About srsLTE that you said, I want to run a TDD-LTE setup and for that, I think about 6 months ago I checked srsLTE, and I couldn’t find any things about running srsLTE in TDD mode.

If you and anybody else have any suggestions about creating a TDD-LTE setup or the problem that I said, I will be thankful to hear them.