diff --git a/doc/UL_MIMO.md b/doc/UL_MIMO.md
new file mode 100644
index 0000000000..6adf5f2790
--- /dev/null
+++ b/doc/UL_MIMO.md
@@ -0,0 +1,88 @@
+# UpLink Multiple Input Multiple Output (UL MIMO)
+## What is UL MIMO ?
+
+UpLink MIMO refers to the use of multiple antennas at both the UE (User Equipment) as transmitter and the base station as receiver. They are used to send multiple data streams simultaneously from the user to the network.
+
+## How to use it ?
+
+## Step 1: build phy sim
+
+```bash
+cd cmake_targets/
+sudo ./build_oai --phy_simulators -c
+cd phy_simulators/build/
+```
+
+## Step 2: Use the sim
+
+### Option 1: launch ULSCH sim  
+On UpLink Shared CHannel(ULSCH), multiple users share the same radio resources (time and frequency slots), the base station schedules and assigns the resources dynamically. The goal here is to simulate the sending of data from an UE to a base station. 
+
+Example:
+| Parameter | Value | Description |
+|--- |:-: |--: |
+| R | 106 | R_NB_UL=106|
+| m | 9 | MCS=9 |
+| s | 13 | Start SNR |
+| n | 100 | Will simulate 100 frames |
+| y | 4 | 4 antennas used in eNB |
+| z | 4 | 4 antennas used in UE |
+| W | 4 | Will use 4 layers |
+
+
+```bash
+sudo ./nr_ulschsim -R 106 -m9 -s13 -n100 -y4 -z4 -W4
+```
+
+### Option 2: launch UL sim
+On UpLink Channel, a single user is dealing with a single base station. The goal is here to simulate the sending of the data from an UE to a base station.
+
+It's focusing on: 
+- UpLink chain validation  
+- PUSCH (whole chain) on UE side and gNB side
+- No channel model on data domain signal, which means an ideal scenario is used
+- No cross-path connection, which means no signal leakage or interference are present
+- PMI = 0  is only unitary precoding matrix
+
+The same parameters are used.
+
+```bash
+sudo ./nr_ulsim -n100 -m9 -r106 -s13 -W4 -y4 -z4   
+```
+### Option 3: Use RFSIM
+
+#### Build
+
+RF simulator allows to test OAI without an RF board. It replaces an actual RF board driver.
+
+```bash
+sudo ./build_oai -c --gNB --nrUE -w SIMU
+```
+
+#### Run
+##### 4x4 RANK 4
+
+Example:
+| Parameter | Value | Description |
+|--- |:-: |--: |
+| O | [...] | Use a configuration file |
+| l | 2 | Set the number of layers for downlink to 2 for PHY test mode |
+| L | 4 | Set the number of layers for uplink to 4 for PHY test mode |
+| ue-nb-ant-rx | 4 | Set UE number of rx antennas to 4 |
+| ue-nb-ant-tx | 4 | Set UE number of tx antennas to 4 |
+
+```bash
+sudo ./nr-softmodem -O ../../../targets/PROJECTS/GENERIC-NR-5GC/CONF/gnb.sa.band78.fr1.106PRB.usrpb210.4layer.conf --rfsim --phy-test --l 2  --L 4
+sudo ./nr-uesoftmodem  --rfsim --phy-test --ue-nb-ant-rx 4 --ue-nb-ant-tx 4
+```
+
+##### 4x4 RANK 2
+
+The same parameters are used excepted uplink number of layers set to 2.
+
+```bash
+sudo ./nr-softmodem -O ../../../targets/PROJECTS/GENERIC-NR-5GC/CONF/gnb.sa.band78.fr1.106PRB.usrpb210.4layer.conf --rfsim --phy-test --l 2  --L 2
+sudo ./nr-uesoftmodem  --rfsim --phy-test --ue-nb-ant-rx 4 --ue-nb-ant-tx 4
+```
+
+
diff --git a/doc/UL_MIMO.txt b/doc/UL_MIMO.txt
deleted file mode 100644
index c06bc78c4c..0000000000
--- a/doc/UL_MIMO.txt
+++ /dev/null
@@ -1,31 +0,0 @@
-# how to build phy sim
-cd cmake_targets/
-sudo ./build_oai --phy_simulators -c
-
-cd phy_simulators/build/
-# ULSCH sim  
-# bit level validation                   
-# PUSCH encoding and decoding for 4 layers   2 CMD without data
-sudo ./nr_ulschsim -R 106 -m9 -s13 -n100 -y4 -z4 -W4
-
-# UL sim
-# Uplink chain validation  
-# PUSCH on UE side and gNB side,whole chain for PUSCH
-# No channel model on data domain signal
-# No cross-path connection
-# PMI = 0  is only unitary prcoding matrix
-sudo ./nr_ulsim -n100 -m9 -r106 -s13 -W4 -y4 -z4   
-
-# How to build rfsim
-sudo ./build_oai -c --gNB --nrUE -w SIMU
-
-# How to run with rfsim
-# 4x4 RANK 4
-sudo ./nr-softmodem -O ../../../targets/PROJECTS/GENERIC-NR-5GC/CONF/gnb.sa.band78.fr1.106PRB.usrpb210.4layer.conf --rfsim --phy-test --l 2  --L 4
-sudo ./nr-uesoftmodem  --rfsim --phy-test --ue-nb-ant-rx 4 --ue-nb-ant-tx 4
-# 4x4 RANK 2
-sudo ./nr-softmodem -O ../../../targets/PROJECTS/GENERIC-NR-5GC/CONF/gnb.sa.band78.fr1.106PRB.usrpb210.4layer.conf --rfsim --phy-test --l 2  --L 2
-sudo ./nr-uesoftmodem  --rfsim --phy-test --ue-nb-ant-rx 4 --ue-nb-ant-tx 4
-
-
-