LTE Handover and NR MIMO support for L2 Simulator

Introduction

1. Introduced 2 eNBs for LTE handover.
2. Default RSSI value is used to trigger handover (channel information provided by proxy).
3. Updated PDCP and RLC layers for handover.
4. CSI Reporting support.
5. Additional hooks and functions for MIMO 2x2 support (This does not include any channel modeling/abstraction).

Setup

Get the source code from OAI

git clone https://gitlab.eurecom.fr/oai/openairinterface5g.git

Checkout episys-lte-handover branch.

cd openairinterface5g
git checkout episys-lte-handover

The following environment variables refer to the respective paths for the openairinterface5g and Multi-Ue-Proxy repo locations; the paths to these folders will be referred to as<PATHTOOAI> and <PATHTOPROXY> respectively.

• <PATHTOOAI> = /path/to/current/directory/openairinterface5g
• <PATHTOPROXY> = /path/to/current/directory/Multi-Ue-Proxy

cd <PATHTOOAI>
source oaienv
cd cmake_targets/
./build_oai --eNB --UE -c

OAI eNB Source

sudo -E ./ran_build/build/lte-softmodem -O ../ci-scripts/conf_files/episci/proxy_rcc.band7.tm1.nfapi.conf \
 --noS1 --node-number 1 --emulate-l1 \
 --log_config.global_log_options level,nocolor,time,thread_id | tee eNB.log 2>&1

OAI eNB Target

sudo -E ./ran_build/build/lte-softmodem -O ../ci-scripts/conf_files/episci/proxy_rcc.band7.tm1.nfapi_target.conf \
 --noS1 --node-number 2 --emulate-l1 \
 --log_config.global_log_options level,nocolor,time,thread_id | tee eNB2.log 2>&1

Multi-Ue-Proxy

git clone https://github.com/EpiSci/oai-lte-5g-multi-ue-proxy.git

cd <PATHTOPROXY>

git checkout github-lte_handover

make -j<number-of-jobs>

number-of-jobs can be based on the number of cores in your PC. Use the -v option to enable virtual time mode.

sudo -E ./build/proxy 1 --lte_handover

OAI UE

cd <PATHTOOAI>
source oaienv
cd cmake_targets/

sudo -E ./ran_build/build/lte-uesoftmodem -O ../ci-scripts/conf_files/episci/proxy_ue.nfapi.conf \
 --L2-emul 5 --nokrnmod 1 --noS1 --num-ues 1 --node-number 1 --num-enbs 2 \
 --log_config.global_log_options level,nocolor,time,thread_id | tee UE.log 2>&1

USE TEST SCRIPT (ALTERNATIVE TO ABOVE)

cd <PATHTOPROXY>
./proxy_testscript.py -u 1 --mode lte_handover