updating doc/RUNMODEM.md

doc/RUNMODEM.md

@@ -56,9 +56,48 @@ oai supports [number of deployment](FEATURE_SET.md) model, the following are tes
 1.  [Monolithic eNodeB](https://gitlab.eurecom.fr/oai/openairinterface5g/wikis/HowToConnectCOTSUEwithOAIeNBNew) where the whole signal processing is performed in a single process
 2. if4p5 mode, where frequency domain samples are carried over ethernet, from the RRU which implement part of L1(FFT,IFFT,part of PRACH),  to a RAU
 
+# 5G NR
 
+As of February 2020, all 5G NR development is part of the develop branch (the branch develop-nr is no longer maintained).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).
+
+### Launch gNB
+
+```bash sudo ./nr-softmodem -O ../../../targets/PROJECTS/GENERIC-LTE-EPC/CONF/gnb.band78.tm1.106PRB.usrpn300.conf```
+
+### Launch eNB
+
+```bash sudo ./lte-softmodem -O ../../../targets/PROJECTS/GENERIC-LTE-EPC/CONF/enb.band7.tm1.50PRB.usrpb210.conf
+
+
+
+## phy-test setup with OAI UE
+
+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.
+
+
+### Launch gNB
+
+```bash sudo ./nr-softmodem -O ../../../targets/PROJECTS/GENERIC-LTE-EPC/CONF/gnb.band78.tm1.106PRB.usrpn300.conf --phy-test```
+
+### Launch UE in another window
+
+```bash sudo ./nr-uesoftmodem --phy-test [--rrc_config_path ../../../ci-scripts/rrc-files]```
+
+## 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.