Failed to config band1 40MHz for quectel-RM500QGL

[Zplusless]

Hi community,

I'm trying to connect the Quectel RM500QGL to a gNB equipped with a USRP-B210. I have successfully set up a connection with band 3 at 30 MHz (config file: usrp_fdd_n3_30MHz.yml.txt). However, according to the official document of Quectel, the RM500QGL supports band 3 with a maximum of 30 MHz and band 1 with a maximum of 40 MHz.

I changed dl_arfcn, srate, and band in the config file (config file: test_fdd_n1_40MHz.yml.txt), but the RM500QGL failed to attach.

gnb log: gnb.log

I'm not sure if the modification is correct. If there are any problems, please point them out. Thanks in advance.

btw：Quectel RM500QGL and gNB are connected with SMA cable and spliter (following the tutorial) like this:

[herlesupreeth]

Can you change the freq back to band 3 and attach the modem and send me the F1AP pcap? I want to check the UE Capabilities information which is a better indication of what BWs UE supports at a particular band

[Zplusless]

Thanks! I have tested n1 40MHz with all log level set to info. The command is sudo gnb -c test_fdd_n1_40MHz.yml -c log_level_info.yaml and the config files and the gnb.log are as follows:

gnb-n1_40MHz-all_level_info.log
log_level_info.yaml.txt
test_fdd_n1_40MHz_.yml.txt

Besides, I have two more questions:

1. Regarding ARFCN, can I set its value to any number that is divisible by 20 within its range?
2. My wireshark cannot decode f1ap.pcap with "user encapsulation not handled: DLT=154". How to solve it? Current I cannot read anything valuable from the pcap file.

[herlesupreeth]

My wireshark cannot decode f1ap.pcap with "user encapsulation not handled: DLT=154". How to solve it? Current I cannot read anything valuable from the pcap file.

Here is the link to a guide to see F1AP packet - https://docs.srsran.com/projects/project/en/latest/user_manuals/source/outputs.html#f1ap

Regarding ARFCN, can I set its value to any number that is divisible by 20 within its range?

I think so. Usually I pick the NR ARFCN at the center of the band

Thanks for the logs. I dont see UE even sending a PRACH, not sure whats wrong there. One thing I notice is the high Rx gain in the gNB configuration file

  tx_gain: 70                                                    # Transmit gain of the RF might need to adjusted to the given situation.
  rx_gain: 60                                                    # Receive gain of the RF might need to adjusted to the given situation. 

[Zplusless]

Thanks! I'll modify the config file and feed back with any update.

[pgawlowicz]

@Zplusless any update on this issue?

[Zplusless]

Sadly, Not solved yet.