Ais Receiver (Depending On Versions); Ais Classes - Icom M506 31 Instruction Manual

9
AIS RECEIVER
About AIS
■
AIS (The automatic identification system) is primarily used for
collision-risk management and navigation safety. It automati-
cally transmits and receives vessel information, such as the
vessel name, MMSI code, vessel type, position data, speed,
course, destination and more. Information is exchanged
among the vessels and/or base stations on the VHF maritime
mobile band. The information helps to identify other nearby
vessels or stations by displaying the received data on a plot-
ter or a radar screen.
Other vessel
(Class B AIS)
Vessel information
Your vessel
(Class B AIS)
79
(Depending on versions)
Other vessel
(Class A AIS)
Base Station

AIS Classes

■
There are seven types of AIS stations; vessels, base stations,
Search and Rescue (SAR), Aids to Navigation (AtoN), Search
and Rescue Transmitter (AIS-SART), MOB (Man OverBoard)
and EPIRB (Emergency Position Indicating Radio Beacon)-
AIS.
There are two classes of AIS units, which are installed on
vessels; Class A and Class B.
Under the Safety Of Life At Sea (SOLAS) convention, all
SOLAS vessels, as described below, are required to install a
Class A AIS transponder:
• Upwards of 300 gross tonnage engaged on international
voyages.
• Passenger vessels, irrespective of size, engaged on inter-
national voyages.
• Upwards of 500 gross tonnage not engaged on international
voyages.
A Class B AIS transponder is designed to be interoperability
with Class A units, but not to impact the Class A network.
Many commercial vessels, and some leisure craft, not clas-
sified as requiring a Class A unit, choose to install a Class B
unit to avoid accidents at sea.