Automatic Identification System (AIS)

Automatic Identification System is a maritime vessel reporting systems which lets other vessels see where others are. It was generally introduced as a backup or supplementary system for radar, which does not work well where there are many obstacles.

The AIS-system is also used by authorities and military as a way of surveillance.

AIS operates by sending out a small message on VHF (161.975MHz or 162.075MHz). This makes it possible for hobbyists to receive these with a VHF-receiver (either a maritime VHF or a radio scanner if it's legal in your country). There are different software out there which makes it possible to decode the transmission on your personal computer.

• AISMon
• GNU AIS
• Shipplotter
• With GNU Radio