Cannot see the 5G network when using pixel 7a and USRP B200

[chonghua1]

I'm using Pixel 7A to test the connection between gNB, which uses USRP B200, but I can't search the 5G network in UE. The output of gNB and CN looks like this:

It seems like the gNB successfuly connect with CN, but doesn't transmit the SIB signal.

[ffxxcad]

Have you had success in connecting other COTS UEs or an Amarisoft UE?

[ffxxcad]

I also recommend you install the 5G Switch App on the phone and select NR only so that the phone only sees 5G Networks when searching.

[chonghua1]

Thank you, I wiil try it!
I have followed the srsRAN tutorial https://docs.srsran.com/projects/project/en/latest/tutorials/source/cotsUE/source/index.html, this is the amf.yaml and nrf.yaml configuration:

[chonghua1]

[ffxxcad]

That tutorial is customized for connecting a Oneplus 8T, which tends to connect better when roaming, thus the PLMN of 90170. However, In my experience the roaming hack is not needed when using Pixel phones.

I would change the amf and nrf configs to match your SIM configuration:

mcc: 001
mnc: 01

[chonghua1]

I have changed the configuration metioned above, but the 5G network still NOT Visible.... I try to use another hackrf to see the spectrum, it seems like no signal there, does this mean the gNB isn't transimitting the SIB broadcast signals properly?

[pgawlowicz]

could you share your gnb config?

[chonghua1]

Dear @pgawlowicz, thanks for the reply, I followed the suggestions of @ffxxcad and changed my USRP's antenna, and the problem has been solved 😄

[Zplusless]

Hi, @chonghua1 , Can you please share how to change the antenna? Thanks!