AIS system
What is AIS:
The UN-organisation, IMO, in its International Convention for the Safety of Life at Sea (SOLAS) requires AIS to be fitted aboard international voyaging ships with gross tonnage (GT) of 300 or more tons, and all passenger ships regardless of size. AIS regularly transmits data on VHF in order to avoid collisions with other ships. It is estimated that more than 40,000 ships currently carry AIS class A equipment. In 2007 (wikipedia), the new Class B AIS standard was introduced which enabled a new generation of low cost AIS transceivers. This has triggered multiple additional national mandates from Singapore, China, Turkey and North America affecting hundreds of thousands of more vessels. The system is partly developed in Sweden and uses the STDMA protocol invented by Håkan Lans.
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