:::warning
# <center><i class="fa fa-cog fa-spin fa-1x fa-fw"></i> [OAI] OAI Layer 1 + USRP </center>
<center>env1:miniPC / env2:Dell Server</center>
:::

:::success
**🎯 Goals:**
:::
### Basic
:::info
**Dell Server**
⚓ **Installation environment:**
- Branch: `Develop`
- OS: Ubuntu 18.04.6 LTS
- CPU: Intel(R) Xeon(R) Gold 6326 CPU @ 2.90GHz core 64
- Stroge: 800GB
- Memory: 188GB
:::

:::info
**env1:miniPC**
⚓ **Installation environment:**
- Branch: `Develop`
- OS: Ubuntu 18.04.6 LTS
- CPU: Intel(R) Core(TM) i7-7567U CPU @ 3.50GHz
- Stroge: 1TB
- Memory: 8GB
:::
### Basic requirement
| OS/Kernel | Version |
|:-------------------------- |:----------------------------------------|
| Host operating system | Linux Ubuntu 18.04 or 20.04 |
| Kernel | 4.15.0.142.lowlatency |
:::info
:bookmark: **Reference:**
- [OSC O-DU at OAI PNF (Rel. D)](https://hackmd.io/JO7qHfZjSmylYSZKokA5Xg?view#Build-OAI-gNB)
- [Script files](https://github.com/dong881/run-integrate_OAIOSC)
- [LOG files](https://github.com/dong881/OSC-DUHigh_OAI-L1)
:::

[toc]

# Change Kernel
**Goal:** `4.15.0.142.lowlatency`

Check curent kernel

uname -r

> 5.4.0-150-generic

Download

sudo apt-get install linux-image-4.15.0.142-lowlatency

Check OS indtalled kernel

dpkg --list | grep linux-image

Check kernel list

grep -E "(submenu|menuentry) " /boot/grub/grub.cfg

> check submenu 'Advanced options for Ubuntu' ID
> check menuentry 'Ubuntu, with Linux 4.15.0-142-lowlatency' ID


Edit file

sudo nano /etc/default/grub

- Find `GRUB_DEFAULT=1` and changes into

GRUB_DEFAULT="gnulinux-advanced-02051e5b-e6dc-4364-9531-869c95a70f94>gnulinux-4.15.0-142-lowlatency-advanced-02051e5b-e6dc-4364-9531-869c95a70f94"

> You need to change to your ID [color=pink]

Update GRUB

sudo update-grub

Change default kernel

sudo grub-set-default '4.15.0-142-lowlatency'

**Reboot**

Check OS kernel now

uname -r


# Install UHD （USRP Hardware Driver）

sudo apt-get update
sudo apt-get install libuhd-dev

uhd_find_devices


# Build OAI gNB
#### Clone and build the dependency for the first time

cd openairinterface5g/

# Build ONLY FOR the FIRST time
source oaienv
cd cmake_targets
export BUILD_UHD_FROM_SOURCE=Ture
# export UHD_VERSION=4.3.0.0-rc1
# we upgrade to 4.5.0
export UHD_VERSION=4.5.0
# ./build_oai -I -c -C -w USRP --gNB
./build_oai -I -c -C
./build_oai -w USRP --gNB

**BUILD SHOULD BE SUCCESSFUL**

### RUN OAI

cd ran_build/build
sudo ./nr-softmodem -O [where the config file is] --sa -E --gNBs.[0].min_rxtxtime 6 --nfapi 1 # 1 : PNF, 2 : VNF
    
sudo ./nr-softmodem -O ../../../../odu_at_oai/l2/mwnl/oai_pnf_conf/oaiL1.nfapi.usrpb210.conf --sa -E --gNBs.[0].min_rxtxtime 6 --continuous-tx --nfapi 1

# e.q. sudo ./nr-softmodem -O ../../../../../odu_at_oai/l2/mwnl/oai_pnf_conf/oaiL1.nfapi.usrpb210.conf --sa -E --gNBs.[0].min_rxtxtime 6 --continuous-tx --nfapi 1
# --gNBs.[0].min_rxtxtime 6 --> To ensure that the rx tx time advance is 6 slots




# Wireshark
setting

nfapi

# Trace Log

| nFAPI | P5 | P7 |
| ----- | ------------------- | --- |
| No.1 | PNF_PARAM.request | |
| No.2 | PNF_PARAM.response | |
| No.3 | PNF_CONFIG.request | |
| No.4 | PNF_CONFIG.response | |
| No.5 | PNF_START.request | |
| No.6 | PNF_START.response | |

## message sequence chart (MSC) of P5

VNF->PNF:PNF_PARAM.request
PNF->VNF:PNF_PARAM.response
VNF->PNF:PNF_CONFIG.request
PNF->VNF:PNF_CONFIG.response
VNF->PNF:PNF_START.request
PNF->VNF:PNF_START.response

> VNF: OSC DU High
> PNF: OAI Layer 1

# IP and port


# Additional

Performance


<style>
.title {
color: #009933;
font-weight:bold;
}
.highlight {
color: #ff4d4d;
font-weight:bold;
border-bottom:2px red solid; padding-bottom:2px;
}
</style>
<!-- <font class="highlight"> -->
<!-- <font class="title"> -->
<!-- 縮寫提示 -->
<!-- *[O-RAN]:Open Radio Access Network -->