NR Custom Frequency
This tutorial show you how to define NR band and earfcn which is not defined in 3GPP. Amarisoft SDR can roughly support any frequency between 500Mhz and 6 Ghz without any external Up/Down converter. So you can set any frequency within that range regardless of whether it is defined in 3GPP or not.
If any specific frequency and band is defined in 3GPP, you can just specify the band and earfcn as specified in 3GPP. But if you want to use any other frequency region which are not defined in 3GPP, you can define your own band and earfcn as will be shown in this tutorial.
Table of Contents
- NR Custom Frequency
Test Setup
I would not use the UE here since commercial UE would not support non-3GPP band and earfcn.
Key Configuration Parameters
Followings are important configuration parameters for this tutorial. You may click on the items for the descriptions from Amarisoft documents.
Configuration
I am using gnb-sa-custom-band.cfg which is copied and modified from gnb-sa.cfg
I added a new TDD flag option as shown below.
Then I defined my own band and earfcn as below. (
Then I specified an earfcn defined in my own frequecy table. Here I set the band to the custom band that I defined above and pick one of the dl_nr_arfcn and ul_nr_arfcn values that falls into the range of the custom frequency range that I set above.
Run and Check
I cannot provide any test result with commercial UE since commercial UE would not support the custom band.
Just run the LTE service and go to enb screen mode. You can confirm that the band and frequency from the default print out from (enb) screen. If you run [cell phy] command, you can confirm the ARFCN configuration as well.
Same as in the default print out of (enb) screen, you can check the frequency with rf_info command.
Lastly you can confirm that the band you defined is broadcast in SIB1 message as shown below. Confirm that frequencyBandIndictorNR and subcarrierSpacing in SIB1 is set to the value as you set in your configuration file.
