Reliable Perception When It Matters: 4D Imaging Small Target Radar for Safer Navigation

China’s Ministry of Transport, Ministry of Industry and Information Technology, State-owned Assets Supervision and Administration Commission of the State Council, and State Administration for Market Regulation recently issued the Smart Shipping 2030 Action Plan, establishing an overarching policy framework for the development of smart shipping.

The plan emphasizes that smart shipping can improve navigational safety, operational efficiency, and environmental performance, while providing an important application area for developing new quality productive forces. Driven by both policy direction and industry demand, strengthening navigational safety while reducing costs and improving operational quality and efficiency has become a critical priority for the smart shipping sector.

Perception serves as the “eyes” of an autonomous vessel. Its detection performance and reliability directly affect the quality of navigational decision-making.

As an early innovator in maritime autonomy, BOTIX focuses on the practical challenges of complex waterway environments. Its in-house-developed 4D Imaging Small Target Radar is designed to address capability gaps in conventional marine sensing equipment. The system provides accurate, all-weather detection of small targets at close range, strengthening the perception foundation for safer vessel operations.

Conventional X-band navigational radar, while widely used for shorter-range detection, may experience performance limitations within approximately one nautical mile. Sea clutter can increase false alarms and missed detections, while limited resolution makes smaller targets more difficult to distinguish. In high sea states, weak returns from small targets are particularly likely to be masked by sea clutter.

BOTIX’s 4D Imaging Small Target Radar uses decimeter-level range resolution to resolve target contours and shoreline features more clearly. It can detect navigational marks, small fishing vessels, buoys, and even persons in the water, including small targets that may be difficult for conventional navigational radar to resolve reliably.

Advanced algorithms filter interference from waves, rain, snow, and system noise, allowing the radar to maintain cleaner and more stable perception output under complex operating conditions.

Stable Detection of a 16-Metre Pilot Boat

In the test shown above, the target was a 16-metre pilot boat, with the visual-camera image displayed in the lower-right corner.

Under the test conditions, the conventional X-band navigational radar showed relatively large deviations in its range estimates. The target return began to fluctuate at a range of approximately 300 metres and disappeared when the distance decreased to around 100 metres.

By comparison, the BOTIX 4D Imaging Small Target Radar maintained stable and continuous detection of the target throughout the test within a range of 500 metres.

Clearer Shoreline Contours

In the shoreline detection comparison shown above, the conventional X-band radar produced a broad area of indistinct shoreline echoes, making detailed shoreline features difficult to identify.

The BOTIX 4D Imaging Small Target Radar reproduced the shoreline contour more clearly, providing a more precise reference for understanding shoreline boundaries during coastal and close-range operations.

Automated Detection and Tracking

Conventional radar operation can depend heavily on manual parameter adjustment and operator interpretation, making it more difficult to support the future requirements of smart shipping.

Key radar operating and filtering parameters on the BOTIX 4D Imaging Small Target Radar are optimized automatically, without requiring frequent manual adjustment by the crew. Target acquisition and tracking are also automated, allowing bridge personnel to focus more attention on navigation, situational awareness, and overall vessel operations.