{"id":3308,"date":"2020-05-27T15:44:32","date_gmt":"2020-05-27T15:44:32","guid":{"rendered":"https:\/\/open-cells.com\/?p=3308"},"modified":"2020-07-23T09:37:23","modified_gmt":"2020-07-23T09:37:23","slug":"5g-openair-first-run","status":"publish","type":"post","link":"https:\/\/open-cells.com\/index.php\/2020\/05\/27\/5g-openair-first-run\/","title":{"rendered":"5G OpenAir first run"},"content":{"rendered":"\n

version: update July, 23rd 2020<\/p>\n\n\n\n

Tutorial to run 5G OpenAir, from current develop branch.<\/p>\n\n\n\n

OAI 5G is very partial, only a fixed scheduler, for one UE, no network entry (no radio network entry, no upper layers network entry). <\/p>\n\n\n\n

We can use “phy-test” mode, that hard code a permanent UL and DL shared channel (means a data channel dedicated to one UE in 3GPP jargon).<\/p>\n\n\n\n

Of course there is no core network in this very special “phy-test” mode and some upper layer pieces are still 4G (PDCP for example).<\/p>\n\n\n\n

Please read the 4G tutorial for more information on how to make initial installation of OpenAir.<\/p>\n\n\n\n

Then, you can compile and run 5G tests<\/p>\n\n\n\n

To compile:<\/p>\n\n\n\n

.\/build_oai --gNB --nrUE<\/pre>\n\n\n\n
Run the gNB in one windows<\/p>\n\n\n\n
sudo .\/nr-softmodem -O ..\/..\/..\/ci-scripts\/conf_files\/gnb.band78.tm1.106PRB.usrpn300.conf --parallel-config PARALLEL_SINGLE_THREAD --rfsim --phy-test --rfsimulator.serveraddr server --noS1 -d<\/pre>\n\n\n\n
If you use the same machine for the UE, we have the same IP address problem as in 4G (see our post rf-simulator-and-oai-ue-tutorial<\/a>)<\/p>\n\n\n\n
so, create a new Linux namespace as in this tutorial<\/p>\n\n\n\n
In the namespace, run<\/p>\n\n\n\n
sudo .\/nr-uesoftmodem -d --rrc_config_path . --nokrnmod --phy-test --rfsim --rfsimulator.serveraddr 10.200.1.1 --noS1<\/pre>\n\n\n\n
If it runs fine, you should see this graph:<\/p>\n\n\n\n
\"\"<\/figure>\n\n\n\n
If the graph doesn’t show working PDSCH, restart the UE as there is a random bug in UE initial synchronization.<\/p>\n\n\n\n
Then, open one more text window and set it in the UE network name space<\/p>\n\n\n\n
sudo ip netns exec ueNameSpace bash<\/pre>\n\n\n\n
It is now possible to ping the gNB output interface<\/p>\n\n\n\n
ping -I oaitun_ue1 10.0.1.1 -s 1000<\/pre>\n\n\n\n
Sends in both directions packets of 1000 bytes.<\/p>\n\n\n\n
Ping also checks the packet content is the same.<\/p>\n\n\n\n
What is today available on top of this simple tutorial:<\/p>\n\n\n\n