Table of Contents:

How to build the eNB and the UE
How to run an eNB built with the noS1 option
How to run a UE built with the noS1 option
Continuous Integration notes
How to ping an eNB from a UE and vice versa (with the noS1 option)

The old oaisim is dead! Long live oaisim! :)

If you are looking for a description of the old oaisim (which is still available in some branches/tags), please see here and here.

oaisim has been scraped and replaced by the same programs that are used for the real-time operation, lte-softmodem and lte-uesoftmodem. The latter also now includes an optional channel model, just like oaisim did.

How to build the eNB and the UE 

The following paragraph explains how to run the L1 simulator in noS1 mode and using the oai kernel modules.

How to run an eNB with the noS1 option 

Modify the configuration file for IF4p5 fronthaul, /openairinterface5g/ci-scripts/conf_files/rcc.band7.nos1.simulator.conf, and replace the loopback interface with a physical ethernet interface and the IP addresses to work on your network. Copy your modifications to a new file, let’s call YYY.conf the resulting configuration file.

Run lte-softmodem as usual with this configuration.

$ source oaienv
$ cd cmake_targets/tools
$ sudo -E ./init_nas_nos1 eNB
$ cd ../ran_build/build
$ sudo -E ./lte-softmodem -O YYY.conf --noS1 --nokrnmod 0

How to run a UE with the noS1 option 

Similarly modify the example configuration file in /openairinterface5g/ci-scripts/conf_files/rru.band7.nos1.simulator.conf and replace loopback interface and IP addresses. Copy your modifications to a new file, let’s call XXX.conf the resulting configuration file.

Run it like:

$ source oaienv
$ cd cmake_targets/tools
$ sudo -E ./init_nas_nos1 UE
$ cd ../ran_build/build
$ sudo ./lte-uesoftmodem -O XXX.conf -r 25 --siml1 --noS1 --nokrnmod 0

That should give you equivalent functionality to what you had with oaisim including noise and RF channel emulation (path loss / fading, etc.). You should also be able to run multiple UEs.