CSI Data Collection Using ESP32

Course: ELE529E Embedded Systems
Objective: Real-time CSI data collection and visualization using ESP32 and FreeRTOS

Features

• Real-time CSI data collection using ESP32
• FreeRTOS-based task management
• Web-based real-time visualization
• Configurable subcarrier selection
• Data logging and export functionality

Project Structure

├── main/
│   ├── main.c              # ESP32 firmware with FreeRTOS implementation
│   └── CMakeLists.txt
├── web_app.py             # Python web application for visualization
├── CMakeLists.txt
└── README.md

Hardware Requirements

• ESP32 Development Board
• USB-to-Serial Cable
• Computer for running web visualization
• Wi-Fi Access Point

Software Requirements

• ESP-IDF v5.4
• Python 3.x with Flask
• Web Browser (Chrome recommended)

Setup Instructions

ESP32 Setup

1. Install ESP-IDF v5.4
2. Clone this repository
3. Configure your WiFi credentials in sdkconfig

# ESP32 CSI Collection Tool Config
CONFIG_SSID="myssid"
CONFIG_PASSWORD="mypassword"
# end of ESP32 CSI Collection Tool Config

5. Build and flash the firmware:

idf.py build
idf.py -p (PORT) flash

or in VS Code, Command+Shift+P > Select 'ESP-IDF: Build Project' > Flash ! DO NOT monitor as doing so will block web application's access to serial port

Web Application Setup

1. Install Python dependencies:

pip install flask pyserial

2. Run the web application:

python web_app.py

3. Open your browser and navigate to http://localhost:5000

FreeRTOS Implementation

The project uses FreeRTOS for efficient task management:

• WiFi Initialization Task (Priority: 5)
• CSI Processing Task (Priority: 3)
• Inter-task communication using queues
• Task synchronization using semaphores

Usage

1. Connect to ESP32 through the web interface
2. Start CSI data collection
3. Select subcarriers to plot
4. Observe real-time CSI data visualization
5. Export data for analysis

Troubleshooting

• If seeing squiggly lines, clean the build, then build again till succeeds. This usually solves ESP-IDF library problems.
• If there are include errors related to cmake, disable the "cmake tools" extension on VS Code.
• If encounter any other problem: Delete the build folder completely, then rebuild
• Make sure ESP32 is connected to an access point. The ESP32 does not work in monitor mode in this project, it needs to be connected.

Useful Resources

• ESP-IDF Documentation
• ESP32 CSI Documentation
• FreeRTOS Documentation
• How to create your First ESP IDF project
• https://github.com/espressif/esp-csi
• Getting Started with ESP32 Wireless Networking in C

Contributing

Feel free to submit issues and enhancement requests!

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