Detecting small targets in busy waters is essential for search and rescue missions, where identifying hard-to-spot objects can mean the difference between life and death. Traditional methods, such as scanning with binoculars, are time-consuming and often ineffective in covering large areas like rivers, harbours, estuaries, and coastal regions. In these scenarios, small and distant targets are easily missed, and delays in spotting individuals can prove to be fatal. To enhance situational awareness and improve detection accuracy and speed, integrating advanced technology with current operations is vital. This hybrid approach, combining human vigilance with cutting-edge radar technology, has the potential to save lives by ensuring no target goes unnoticed.
Current camera-based systems have limitations: they can only cover small fields of view and are practically effective up to 150 metres. Moreover, they struggle in changing light conditions and adverse weather, such as glare at sunset or during dark, rainy days. While traditional navigation radars are adept at detecting large vessels, they lack the resolution required for noticing smaller surface objects.
High-resolution marine radar technology addresses these challenges, complementing traditional human methods while providing enhanced detection capabilities in all lighting and weather conditions. W-band radars, equipped with a 360° field of view, are equivalent to the coverage of multiple cameras, while operating seamlessly day or night, regardless of the weather. Their superior resolution enables the detection and tracking of smaller objects, even in congested and cluttered environments, that traditional X-band radars might miss. This technology supports operators by allowing the radar to direct human intervention with pinpoint accuracy, such as guiding a spotlight or controlling a floodlit camera. Additionally, if an operator loses sight of an object, the radar can maintain a lock on the target for distances up to 100 metres in all directions, a crucial feature in time-sensitive, high-stakes scenarios, such as river rescues where strong currents can quickly carry people away.
High-resolution Navtech radars play a crucial role in search and rescue operations by enabling clear mapping and simplifying the target identification process. Mounted on a boat, the radar provides a condensed, real-time view of the surroundings as the vessel moves along waterways, offering a comprehensive view covering an area of 1.13km2. Once a person in distress is identified, operators can pinpoint their exact location using chart plotter overlays, facilitating precise and rapid response.
The radar’s continuous tracking capability allows operators to head directly to the person in distress rather than their last known position, which is often the case when relying solely on visual identification. This capability is especially critical in poor visibility conditions, such as at night or during bad weather, ensuring that even objects lost from sight in fast currents, can still be detected and tracked. When the target is reached, the combination of radar-guided searchlights streamlines the rescue process, significantly saving time and potentially lives.
In search and rescue operations across rivers and estuaries, human vigilance alone has its limitations. While experienced operators can quickly recognise dangers over small areas, visibility gaps over larger areas can prove fatal. Integrating radar technology into these operations enhances detection accuracy by covering a 600-metre radius range in an easily interpretable format. This imaging capability effectively addresses challenges posed by poor lighting and adverse weather conditions. Even in thick fog at night, the radar can detect small targets invisible to the naked eye across 1.13km2.
Looking ahead, the potential integration of artificial intelligence (AI) with radar systems could further enhance safety by learning from past trips and rescues, enabling faster danger detection. Key benefits of using high-resolution radar in search and rescue include:
The high-resolution radar operates at a frequency of 76-77 GHz, optimised for better target detection, especially in cluttered environments. With a range resolution of 17 cm and a 1.8° beam, the radar can differentiate between a person in the water and infrastructure. It offers extensive coverage over 1.13km2 and integrates with trackers to derive precise coordinates, range, and bearing of targets. The radar’s single-sensor solution provides complete 360° coverage, eliminating blind spots and ensuring continuous monitoring.
A collaboration between the Metropolitan Police and Navtech Radar has successfully demonstrated the potential of high-resolution radar in search and rescue scenarios. During trials on the River Thames, the RAS6 Navtech Radar was mounted on the bow deck of a Targa 32 patrol boat to evaluate its performance in detecting small targets. The trials involved using both a dummy and a live swimmer to test detection accuracy near large objects, assessing the radar’s ability to filter out sea clutter.
The radar effectively detected the dummy and demonstrated the ability to distinguish it from surrounding noise up to 90 metres away. In a subsequent test, a live swimmer was tracked, with the radar accurately detecting movements as small as a person’s head and shoulders. Remarkably, the radar also identified the splashing motion typical of a distressed swimmer, despite the body’s non-reflective nature and partial visibility. This performance underscores the radar’s superior quality and capability to identify and track small targets in high-noise environments.
“It was pleasure to host Rachel and her team from Navtech Radar and put their new W-band scanner through its paces this week. It was able to deliver high-definition imagery of our environment and the ability to identify and track extremely small targets thanks to its narrow beam radar technology. Could be a game changer in security and SAR operations.” Nick Bultitude, Technical Rescue Team Leader, Metropolitan Police.
Navtech Radar is actively seeking partners within the marine industry to collaborate on proof-of-concept trials using its radar sensor technology for small object detection, target separation, and tracking fast-moving objects. By integrating these advanced radar systems into search and rescue operations, we can significantly enhance the ability to detect and respond to emergencies, ultimately saving lives.