EO Products / AIS, radar signal and other instruments suited for ship detection and monitoring

Business Process

Product Description

The Automatic Identification System (AIS) is an automatic tracking system used primarily for maritime purposes. In fact, it was developed in 1990s, as a collision avoidance tool. It operates via transceivers installed on ships and is also utilized by vessel traffic services (VTS). Ships equipped with AIS transceivers continuously broadcast information such as position, speed, course, and vessel details. Shore stations and satellites receive AIS signals, allowing real-time tracking of vessels. However, AIS data is limited to VHF range (about 10–20 nautical miles). When satellites receive AIS signals, it’s referred to as Satellite-AIS (S-AIS). AIS systems have limited in range. Due to Earth curvature AIS signals cannot travel further than 50 nautical miles. Therefore, at open sea or in areas where costal base stations are limited AIS data can be relayed using satellites. This is invaluable in tracking and monitoring ships in remote areas and open oceans. While S-AIS gives a detailed overview over ships with AIS equipment installed, it can be combined with satellite imagery to detect and identify ships that turns off their AIS or are not equipped with it.   Other instruments can be used for monitoring vessel traffic in the Arctic and Baltic Sea, including:

Radar (Radio Detection and Ranging): Radar predates AIS and provides information on ship positions, distances, and relative speeds. The sensor can operate in various radar modes (e.g., X-band, S-band) and offer varying ranges and resolutions. All ships over 300 GRT are required to be equipped with 9ghz radar, in addition, vessels over 500 GRT requires an automatic tracking aid. Radars are then used to identify, tracking and position vessels to sail safely. The radars are classified under two different bands: X-band (10 GHz) uses high frequencies to create sharp images while S-band (3GHz) tends to work better in foggy and rainy conditions.

Sonar: Sonar is used for underwater surveillance, including detecting ice and underwater objects. Passive sonars register the soundwaves of underwater entities while active sonars emit a pulse and registers the echo or reflection of the pulse.

Vessel Traffic Management Systems (VTMS): VTMS combines radar, AIS data, and other sensor inputs to manage vessel traffic in busy ports and waterways. It can provide real-time information to support safe navigation and traffic flow.

Costal Surveillance Systems: These integrated systems combine various sensors, including radar, AIS, and cameras, to monitor and secure coastal areas, ports, and critical maritime infrastructure.

UAVs: Drones equipped with cameras or other sensors can be used for aerial surveillance of ships and maritime areas. They are especially useful for monitoring illegal fishing and environmental compliance.

Satellites with sensor operating in the optical range:

• High-resolution optical satellite images typically have a sub-meter level resolution. This means that they can resolve details down to less than a meter in size. For ship detection, optical imagery provides clear visual information about ships, their shapes, and other features. Optical technology is widely used for ship detection due to its ability to capture detailed surface features, including ship structures, colors, and patterns.

Satellites with sensor operating in the thermal infrared technology:

• Thermal infrared sensors on satellites have a coarser resolution compared to optical sensors. They typically operate at resolutions ranging from tens of meters to several hundred meters. These sensors detect thermal emissions from objects, including ships, based on their temperature differences. Thermal infrared technology is valuable for detecting ships at night or in adverse weather conditions when visible light is limited. However, it may not provide fine details about ship shapes or individual vessels.

Satellites with sensor operating with radar technology (Synthetic Aperture Radar, SAR):

• SAR operates at various resolutions, depending on the specific satellite system. It can achieve resolutions ranging from a few meters to tens of meters. The higher the frequency of the radar, the finer the resolution. For example, X-band SAR provides better resolution than L-band SAR. SAR is particularly useful for ship detection because it is not affected by cloud cover, darkness, or atmospheric conditions. It can penetrate through clouds and capture ship signatures based on their radar backscatter properties. SAR can detect ships even in rough seas and challenging environments.

Product Specifications

Business Process Challenges

Ship Certification (SCE) Challenges

• SCE-9 Ship Monitoring, Location and Operation

Insurance (IN) Challenges

• IN-1 Incident Investigation

Ship Operation (SO) Challenges 

• SO-11 Monitoring Vessels Without AIS Transponder

End of Life Vessel Disposal (ELD) Challenges

• ELD-3 Authority monitoring of vessels on their way for scrapping