Introduction

The Rd-03L_V2 is an ultra-low power millimeter-wave human presence sensor module developed by Ai-Thinker. It features a simplified 24GHz radar sensor hardware and a low-power human presence detection algorithm firmware.

Equipped with the AloT millimeter-wave sensor SoC ICL1112, a high-performance 24GHz 1T1R antenna, and peripheral circuits, the module utilizes distance measurement technology combined with advanced proprietary radar signal processing and low-power control technology from the ICL1112 chip to accurately detect moving, micro-moving, and stationary human bodies.

This low-power detection algorithm is mainly designed for indoor applications to sense whether there are moving or micro-moving human bodies within the area, continuously updating the detection results in real time under low-power mode.

1. Rd-03L_V2 Appearance and Pin Description

1.1 Appearance Display

1.2 Pin Description

⚠️ Note: The debugging interface and programming interface cannot be used simultaneously.

Debugging Interface (TTL-USB Debugger)

Programming Interface (J-Link Debugger)

2. Rd-03L_V2 Operating Steps

2.1 Download PC Software and Related Materials

Download link: Click to download

Or visit the Ai-Thinker docs page for more resources on Rd-03L_V2: Rd-03 Series

2.2 Module Wiring

2.3 Module Installation

The Rd-03L_V2 radar module is designed for wall-mounted installation at a height of 1.5–2m. The installation orientation is shown below:

• X-axis: 0°,
• Z-axis: 90°,
• Y-axis is perpendicular to the X-Z plane (normal direction).
• Distance reporting frequency: 1–8Hz (max 8Hz);
• Status reporting frequency: multiple of the distance reporting frequency (e.g., if set to 4Hz, status reporting can be 4Hz or 8Hz).
• Test Equipment: KEYSIGHT_N6705C Current Analyzer

When wall-mounted at 1.5m, the default detection range is a conical space with a 6m distance in the normal direction and ±60° angle in the horizontal and pitch directions.

2.4 Quick Setup via PC Software

Note: The Rd-03L_V2 PC software and serial port tool cannot be used simultaneously.

After completing wiring (Step 2) and proper installation (Step 3), open the PC software:

• Refresh the port list (bottom left corner);
• Select the correct COM port;
• Set baud rate to 256000 bps;
• Click Connect Device.

After successful connection, click Auto Threshold Generation.

The radar will scan the environment during this process — ensure no human presence within the detection area during the 120–240 second scan period.

After scanning, the thresholds are applied automatically. Close the window to finish.

After successful threshold generation, the threshold values for each distance gate will change according to the algorithm. Note: Manually adjust the trigger and hold thresholds of distance gates 00 and 01 to around 42 after auto-generation.

Additional settings allow for defining minimum and maximum detection distances (up to 6.3m), adjusting reporting frequencies:

Response time can be set to Normal or Fast to define the time the sensor reacts when a person enters the detection zone. No-person reporting delay: adjustable between 10–120 seconds, determines the delay before switching status from presence to absence.

After adjustment, click Write to Sensor to save...