ESP32 Radar System with RCWL-0516 Microwave Sensor

RCWL-0516 is a microwave Doppler radar sensor that detects moving objects through walls, wood, glass, and plastic unlike PIR sensors which need line-of-sight. ESP32 with RCWL-0516 creates smart presence detection system. Detection range: up to 7 meters, 360-degree omnidirectional. Sensor output goes HIGH (3.3V) when motion detected. ESP32 reads output, tracks detection events with timestamps, calculates occupancy patterns. Features: configurable detection window (ignore brief triggers < 2 seconds), occupancy counter (estimate number of people using detection frequency), integration with Home Assistant via MQTT, Telegram alert on first detection per hour, daily occupancy report via email. Multi-sensor mode: 3 RCWL-0516 sensors at different heights to estimate person height/position. Applications: office occupancy monitoring, elderly care presence monitoring, smart lighting control. Libraries: WiFi, PubSubClient, NTPClient, ArduinoJson.

Detailed Project Description

ESP32 Radar System with RCWL-0516 Microwave Sensor focuses on a specific hardware interface or peripheral and shows exactly how to wire it, drive it from firmware and verify it is working.

How It Works
1. The peripheral is connected to the controller using the required bus (SPI/I2C/UART/I2S/CAN/RS-485/PWM/ADC).
2. The driver library is initialised and the peripheral configured.
3. Firmware exchanges data with the peripheral and processes it (measure, decode, render, play).
4. Results are verified on a display, serial monitor or the receiving device.

Key Components and Their Role
- ESP32: dual-core Wi-Fi + Bluetooth microcontroller that runs the firmware, reads the sensors and hosts the network connection.
- PIR motion sensor: passive infrared sensor that detects human movement.
- RCWL-0516: microwave Doppler radar module that detects movement even through thin walls.
- OLED display (SSD1306): 128x64 I2C display used to show live readings and status.
- MQTT: lightweight publish/subscribe messaging protocol used for IoT data.
- Telegram Bot API: messaging channel used to send alerts and receive commands.

Implementation Steps
1. Collect the components and study each module's datasheet (pin-out, voltage, interface).
2. Wire the circuit on a breadboard following the pin mapping; power sensors from the correct rail (3.3 V / 5 V).
3. Install Arduino IDE, PubSubClient Library, Home Assistant and the required libraries; flash a minimal test sketch for each module separately.
4. Write the main firmware: read sensors → process → drive outputs / send data.
5. Configure network or cloud credentials and test communication end-to-end.
6. Calibrate thresholds, add error handling (reconnect, sensor time-out) and run a long-duration test.
7. Finalise on a PCB / enclosure and document wiring, code and results.

Key Features
- Correct wiring and bus configuration
- Driver setup
- Data processing
- Verification on real hardware

Expected Output
On completion the student will have a working peripheral that is measured/driven exactly as intended.

Deliverables
- Complete source code with comments
- Circuit diagram and pin mapping
- Project report with screenshots and results
- Demonstration-ready build