Space based Automatic Identification System (S-AIS)
Automatic Identification System (AIS) is a shipboard broadcast system that transmits a vessel's identification, position and other critical data that can be used to assist in navigation and improve maritime safety.
During its last mission, astronauts from the Space Shuttle Atlantis installed an Automatic Identification System antenna on the outside of the International Space Station that will allow astronauts aboard the ISS to monitor signals from the AIS transmitters mandated to be installed on most large ocean-going craft.
Although these VHF signals can be monitored from the Earth's surface, their horizontal range is generally limited to about 75 km (46 mi), leaving large areas of the ocean unwatched.
However, the signals easily reach the 400 km (250 mi) orbit of the ISS.
The European Space Agency sees this experiment as a test platform for a future AIS-monitoring fleet of satellites that will eventually provide worldwide coverage of sea traffic."
Some other players on the market propose S-AIS solutions : SpaceQuest, ORBCOMM, ExactEarth (COMDEV Int.), NSC Norwegian Space Centre all have space based AIS systems using NTS, or Nanosatellite Tracking Ships
A space based receiving system for signals of the automatic identification system (AIS) will extend the coverage of the existing ground network, which is limited to the coastal zone to open seas.
With newly available satellite-based AIS receivers, the complete global ocean shipping fleet of about 60,000 ships (AIS Class A) can be tracked.
The safe processing and distribution of satellite-based AIS messages to authorized users by a public traffic monitoring centre will contribute to a significantly enhanced maritime safety and security.
Links :
- BBC : Norway launches AISSat ship-tracking spacecraft
- ORBCOMM : Worldwide AIS data from Space
- ExactEarth : Satellite detection of AIS-SART-EPIRB sea trials
- ESA : Space Station keeps watch on world’s sea traffic
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