Testing a 24G / 77G mmWave Radar for Reliable Distance Sensing on UAV & Robotics

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In low-visibility environments such as night, fog, dust, or complex terrain, vision and LiDAR systems often become unstable.
Millimeter-wave radar works differently. It is independent of light and can provide stable, continuous distance sensing.
Recently, I tested a 24G / 77G mmWave radar module for UAV and robotics applications. Here’s a simple engineering walkthrough covering wiring, setup, and real-world testing.

Radar Overview
The radar uses FMCW technology and supports:

Distance detection
Speed detection
Target tracking

Key specs:

Frequency: 24G / 77G
Detection range: 20–100m (depending on model)
Accuracy: up to ±0.1m
Refresh rate: 33Hz
Interface: CAN / UART
Power consumption: ≤ 2.5W
Voltage: 5–28V DC This makes it suitable for drones, robots, and embedded systems.

Hardware Setup
My test setup includes:

mmWave radar module
Power board (PDB)
6S battery
USB2CAN adapter
Laptop for monitoring

Connection:
Radar → CAN → USB2CAN → PC
Radar → Power → Battery
Pin mapping:
Red — Power+
Black — GND
White — CAN_L / UART_RX
Yellow — CAN_H / UART_TX
The wiring is straightforward and easy to integrate into most flight controllers or robotics platforms.

Installation Tips
Proper mounting is very important.

Keep the antenna facing forward
Avoid metal or carbon fiber blocking the front
Keep wiring short and clean
Slight upward tilt (5°–20°) helps reduce ground clutter Incorrect installation may cause noisy or unstable distance readings.

Testing Steps
Step 1 — Connect the radar using a USB2CAN adapter
Step 2 — Set CAN bitrate to 500 kbps
Step 3 — Open the PC tool and start monitoring
When objects move in front of the radar, distance values update in real time.
You can clearly see targets detected at different ranges such as 2m, 5m, or 10m.

Real-world Performance
From my tests:
Advantages:

Stable in darkness or fog
Works in dust and outdoor environments
Low power consumption
Simple CAN integration
Reliable distance output

Limitations:

Not suitable for high-resolution mapping (LiDAR is better for that)
Requires a clear front view
Needs CAN tools for debugging

Typical Applications
This radar works well for:

UAV obstacle avoidance
Altitude hold
Terrain following
Mobile robots
Industrial automation
Outdoor autonomous platforms It complements vision or LiDAR systems to improve reliability.

Final Thoughts
If your project needs reliable, weather-independent distance sensing, mmWave radar is a solid choice.
It’s not a replacement for cameras or LiDAR, but it greatly improves system stability in challenging environments.
For robotics and UAV developers, it’s a practical and easy-to-integrate sensor worth testing.