Equip Your Boat to Receive AIS Signals
AIS--Automatic Identification System--is a method for transmitting and receiving information about ship traffic. Sharing a vessel's name, location and course, AIS signals supplement radar systems and allow boats to communicate and avoid collisions. AIS receivers and transmitters are required for all ships carrying more than 300 tons of cargo and for all passenger vessels. In recent years, those boats not falling into these categories have been given the option of using Class B AIS, which is inexpensive and allows people to view AIS information without being obliged to transmit it. The steps below will guide you through the simple process of adding an AIS receiver to your boat.
Steps
- Purchase a basic AIS receiver.
- These are much simpler than AIS transmitters and should not cost more than a few hundred dollars.
- Purchase a VHF antenna, or a VHF splitter, if you already have an antenna.
- VHF (very high frequency) radio is the method by which AIS signals are transmitted. Many boats are already equipped with a VHF antenna, in which case you can either split the antenna or mount an additional one.
- Because AIS transmitters work through radio, an extra display unit is needed to present the information graphically. A simple AIS will suffice, although there is also lots of software, including the free SeaClear, that will present the information on a computer.
- Purchase an AIS display or software to display AIS information on a computer.
- Mount the VHF antenna or splitter.
- The antenna should sit about 100 feet (or 30 m) above the surface of the water.
- Install the AIS receiver in the cabin of your boat.
- Connect the AIS display or computer to the AIS receiver.
- Turn on the AIS receiver to begin receiving information from other AIS-equipped vessels in the area.
Tips
- If you want to transmit as well as receive, a Class B AIS transmitter will allow you to contact other AIS-equipped vessels, aiding with navigation. You will not, however, receive or transmit as detailed information as that included with Class A AIS transmission.
- For boats with little room on the deck, splitting a single VHF antenna is probably easier than installing a second antenna. Likewise, it may be possible to purchase a VHF antenna that is already AIS-equipped. If you have the option of easily mounting a second VHF antenna, however, this is a better idea than splitting, as your signal strength will be greater, aiding both AIS and radio transmissions, and a splitter will cost more than an additional antenna.
- Although AIS signals provide much of the same information as radar, as well as additional details, it's a good idea to use both tools in conjunction. AIS does not reveal information about the weather, as radar does, and can be limited in range.
Warnings
- Do not attempt to connect your AIS receiver into an existing VHF radio antenna without splitting. Because a single, non-split antenna cannot handle transmissions to both a radio and an AIS system, your AIS receiver will blow out when you use the radio.
Things You'll Need
- AIS receiver
- VHF antenna or VHF antenna splitter
- AIS display or display software
