Rocks & mirror
Encyclopedia of Marine and Energy Technology

Automatic Identification System (AIS)


A novel radar-based system displaying ship’s unique identification numbers alongside the radar vectors. AIS equipment consists of a central unit that collates information from the ship’s navigation systems with preprogrammed information about the ship’s identity and dimensions and additional information such as voyage details. The information is transmitted automatically to other ships and coastal VTS by way of transponder operating in the VHF marine band. The new AIS requirements have entered into force under amendments to the Solas Convention on July 1, 2002, when new ships of 300 gross tonnage and over engaged in international voyages will have to install the device.