- AIS Marine: Not compulsory in recreational navigation, but very helpful -
An AIS transponder (also known as an AIS transceiver) receives and transmits dynamic and static data of all nearby AIS-equipped vessels and other voyage-related information via two different VHF frequencies. The system is primarily used for collision prevention. Range is limited to the VHF band and averages around 15 nautical miles for sailing yachts, depending on antenna power and mounting height.
Static data are for example vessel name, vessel dimensions as well as vessel type, call sign, MMSI and IMO number. Dynamic data is the navigation status (at anchor, moored or underway), speed over ground, course over ground and position. Useful voyage data informs about the next port, planned arrival time, cargo, etc.
The advantages for recreational boating are that a skipper can easily radio another vessel whenever there is uncertainty in a particular situation. When you buy an AIS system, it enables you to navigate with foresight in, for example, narrow shipping lanes. Warning signals can be set in the respective navigation software to provide indications of an impending collision or to indicate an important turning point. Furthermore, an AIS boat you have made contact with can be tracked on your screen or you can check your destination port occupancy in advance.
Many recreational boaters use just an AIS receiver to get relevant data. The disadvantage here is that a receiver cannot send data. In addition to AIS transceivers and AIS receivers, so-called AtoN transceivers (Aids to Navigation) are in use. These transceivers are frequently mounted on buoys or other shipping hazards and transmit information about their location to nearby vessels.
In addition to the AIS system, software companies such as MarineTraffic and Vesselfinder provide AIS tracking apps. They perform similar functions to the permanently installed devices on board, but are less reliable because, unlike AIS devices, apps use private land receivers. These transmitting stations can fail and display data incorrectly. For their own safety, owners should therefore buy AIS equipment.
- The data transmission of an AIS device works via VHF frequencies.
The automatic identification system uses VHF marine radio. The AIS transceiver transmits coded data for global use on the channels AIS 1 (161.975 MHz) and AIS 2 (162.025 MHz). The software used by the receiver decodes this data and displays it as text or image information on a screen or chartplotter.
Commercial shipping uses Class A AIS with a transmission power of up to 12.5 watts and SODTMA technology (allocation of transmission frequencies via a complex system). In recreational navigation, Class B AIS and only two watts of transmitting power with CSTDMA technology (seeks free time slots for data transmission) is used.
If a VHF antenna is installed on board, it can be used for AIS reception. You only need a splitter so that the data of other connected devices can be operated with the respective power specification without overheating.
If an additional AIS antenna is to be used, it must be mounted at least three metres away from the existing antenna and at the highest possible height. In addition to an antenna (and splitter), you will need an AIS output device such as a chartplotter that can be connected to NMEA2000. If you wish to display data on a PC or laptop, a USB interface is all that is needed to connect to an AIS receiver.
In order to display the received data, in addition to the output device, you need appropriate software that decodes the information.
- Safety at sea without charge -
Transmitting and receiving in the AIS system is free of charge and does not require any special authorisation, for example from the Federal Network Agency. This means there are no costs apart from the necessary equipment. AIS equipment such as transceivers, transponders or receivers and, if necessary, antennas and cables can cost between a few hundred and several thousand euros. Budget up to 500 Euros for an AIS receiver, up to 3000 Euros for an AIS receiver / transmitter.
When you buy an AIS system, you should also choose the right accessories. In our various shop categories, you'll find other useful products such as VHF Antennas, Deck Seals and Cable Glands, Radar Units or Network/NMEA2000 (to connect AIS to a display or chart plotter). Before you buy AIS, you should take a look at our guide "Everything there is to know about AIS", where you will find a lot of helpful information.
Sandi F. on 24.03.2023
I would order from SVB again
Ali H. on 24.03.2023
Christian L. on 24.03.2023
Glad i got my stuff in time before the wekend