October 30, 2024
Skrevet av
Tomas Roaldsnes
Terrestrial AIS collects signals via land-based receivers, typically with a range of 30-50 nautical miles from the coast. This provides excellent coverage in busy coastal areas but doesn't extend far out to sea.
Advantages: Precise coverage near the coast.
Disadvantages: Limited range.
SAT-AIS uses satellites to receive AIS signals over long distances, including far out at sea. Coverage depends on the number of satellites in orbit and their position. More satellites in low earth orbit (LEO) provide better coverage, as they pass more frequently over different areas.
Advantages: Global coverage, must-have for ocean-going vessels.
Disadvantages: Higher cost, often delay in position updates.
Dynamic or roaming AIS involves vessels collecting AIS data via VHF and forwarding it, providing extra coverage in high-traffic areas. This extends coverage in ocean areas with many vessels contributing to collecting and sharing data.
Advantages: Flexible, good coverage in areas with high maritime traffic.
Disadvantages: Variable coverage depending on vessel traffic.
Good SAT-AIS coverage depends on the number of satellites and when they orbit over the vessels. More satellites in low earth orbit means more frequent updates, providing more continuous and precise data.
Good position update frequency is crucial for quick response when a vessel shoots off or changes course. It's also important for historical tracking with detailed vessel tracks.
Catchwise is specifically designed for fishing vessels and offers terrestrial, dynamic, and satellite-based AIS.
In addition to AIS, Catchwise offers several fishing-specific features such as estimated bottom temperatures, historically productive areas, and catch forecasts for recommended areas.
Advantages:
· Excellent AIS coverage
· Combines AIS from multiple providers
· Terrestrial, satellite, and roaming
· Customizable vessel tracks
· Weather, wind, and ocean currents
· Estimates fishing activity based on AIS
· Depth contours, seabed, and nautical charts
· Boundaries, fishing banks, and fjord lines
· High focus on user experience
· Detailed ice maps from satellite images
Disadvantages:
· Not global coverage like general AIS services
· Shows only fishing vessels and fishery-related vessels
Source: Screenshot from video on Fishfacts.com
Fishfacts is a popular AIS service for fisheries and aquaculture. The service offers good AIS coverage with both terrestrial and satellite-based AIS.
Fishfacts has numerous features for fisheries such as weather, wind, and ocean currents, as well as sea conditions. The platform also has several other modules for fisheries and aquaculture, including CRM, profitability analysis, and service provider overview.
Advantages:
· Good AIS coverage
· Ability to customize vessel tracks by speed or different vessels
· Weather, wind, and ocean currents
· Option for seabed as background map
· Detailed ice maps from satellite images
Disadvantages:
· Somewhat poorer user experience
· Fewer supporting functions for fishing
Source: Screenshot from Marinetraffic.com
MarineTraffic is one of the most well-known AIS services globally and offers terrestrial and satellite-based coverage through partners. This provides flexible coverage at a reasonable price.
Advantages:
· Good global coverage
· Excellent coastal coverage from terrestrial AIS
· Historical vessel tracks with playback
· Good tracking if you only need to monitor one vessel at a time
· Affordable subscription for a single user
Disadvantages:
· Very poor satellite AIS coverage
· Unsuitable for ocean-going fishing vessels
· Cannot view multiple tracks simultaneously
· No supporting functions for fishing
Source: Screenshot from Vesselfinder.com
VesselFinder provides a simple and user-friendly solution with both terrestrial and satellite-based AIS coverage. The service is ideal for those who only need basic tracking without extra features.
Advantages:
· Somewhat better satellite coverage than MarineTraffic
· Global coverage
· Reasonable price for basic functionality
Disadvantages:
· Cannot view multiple tracks simultaneously
· No supporting functions for fisheries