As of February 2020, all 5G NR development is part of the develop branch (the branch develop-nr is no longer maintained). This also means that all new development will be merged into there once it passes all the CI.
## NSA setup with COTS UE
This setup requires an EPC, an OAI eNB and gNB, and a COTS Phone. A dedicated page describe the setup can be found [here](https://gitlab.eurecom.fr/oai/openairinterface5g/wikis/home/gNB-COTS-UE-testing).
The OAI UE can also be used in front of a OAI gNB without the support of eNB or EPC. In this case both gNB and eNB need to be run with the --phy-test flag. At the gNB this flag does the following
- it reads the RRC configuration from the configuration file
- it encodes the RRCConfiguration and the RBconfig message and stores them in the binary files rbconfig.raw and reconfig.raw
- the MAC uses a pre-configured allocation of PDSCH and PUSCH with randomly generated payload
At the UE the --phy-test flag will
- read the binary files rbconfig.raw and reconfig.raw from the current directory (a different directory can be specified with the flag --rrc_config_path) and process them.
- --ue-fo-compensation: enables the frequency offset compenstation at the UE. This is useful when running over the air and/or without an external clock/time source
- --usrp-args: this is the equivalend paramter of sdr_addrs field in the gNB config file and can be used to identify the USRP and set some basic paramters (like the clock source)
- --clock-source: sets the clock-source (internal or external).
- --time-source: sets the time-source (internal or external).
## noS1 setup with OAI UE
Instead of randomly generated payload, in the phy-test mode we can also inject/receive user-plane traffic over a TUN interface. This is the so-called noS1 mode.
This setup is described in the [rfsimulator page](../targets/ARCH/rfsimulator/README.md#5g-case). In theory this should also work with the real hardware target although this has yet to be tested.
