Si-tex SAS-300, Operation Manual

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About your AIS class B transeceiver
2 About your AIS class B transceiver
2.1 About AIS
The marine Automatic Identification System (AIS) is a location and vessel information reporting system.
It allows vessels equipped with AIS to automatically and dynamically share and regularly update their
position, speed, course and other information such as vessel identity with similarly equipped vessels.
Position is derived from the Global Positioning System (GPS) and communication between vessels is
by Very High Frequency (VHF) digital transmissions.
There are a number of types of AIS device as follows:
•
Class A transceivers.
These are similar to class B transceivers, but are designed to be fitted to
large vessels such as cargo ships and large passenger vessels. Class A transceivers transmit at a
higher VHF signal power than class B transceivers and therefore can be received by more distant
vessels. They also transmit Class A transceivers are mandatory on all vessels over 300 gross
tonnes on international voyages and certain types of passenger vessels under SOLAS regulations.
•
Class B transceivers.
Similar to class A transceivers in many ways, but are normally lower cost due
to the less stringent performance requirements. Class B transceivers transmit at a lower power and at
a lower reporting rate than class A transceivers.
•
AIS base stations.
AIS base stations are used by Vessel Traffic Systems to monitor and control the
transmissions of AIS transceivers.
•
Aids to Navigation (AtoN) transceivers.
AtoNs are transceivers mounted on buoys or other
hazards to shipping which transmit details of their location to the surrounding vessels.
•
AIS receivers.
AIS receivers will generally receive transmissions from class A transceivers, class B
transceivers, AtoNs and AIS base stations but do not transmit any information about the vessel on
which they are installed. This product is an AIS Class B transceiver.
2.2 Static and dynamic vessel data
There are two categories of information transmitted by an AIS transceiver: static and dynamic data.
The vessel's dynamic data, which includes location, speed over ground (SOG) and course over
ground (COG), is calculated automatically using the internal GPS receiver.
Static data is information about the vessel which must be programmed into the AIS transceiver. This
includes:
• Maritime Mobile Service Identity (MMSI)
• Vessel name
• Vessel call sign (if available)
• Vessel type
• Vessel dimensions
In most countries the operation of an AIS transceiver is included under the vessel's marine VHF
licence provisions. The vessel on to which the AIS unit is to be installed must therefore possess a
current VHF radiotelephone licence which lists the AIS system, vessel Call Sign and MMSI number.
An MMSI number is required in order for the AIS transceiver to operate. Please
contact the rlevant authority in your country for more information! .