AIS Explained
AIS stands for Automatic Identification System. This system allows boat names and sizes to show up on a screen. There is a standard interface for the AIS units that allows for target presentation on various radars.
Class A AIS has been required on most classes of commercial vessels for some years now. More and more ports require AIS, especially since 911. So Class A receive only units have been popular on pleasure boats for some time. The Furuno FA150 is the workhorse of the industry. It has a display and a transponder unit.
Class B AIS is new. Designed for pleasure craft, this was started up in 2008. There are both transponder units and receive only units for class B also. Eventually, most boats will have these devices and you will be able to see the names and types of boats around you on your radar display
One of the unexpected benefits of AIS is that commercial vessels are much more likely to contact you by VHF if they know the name of your vessel. This is great in tight quarters with a larger vessel.
A transponder unit requires a separate VHF antenna, while a receive only unit is generally rigged to the existing VHF antenna.
