Before installing an AIS splitter, read our guide explaining when a dedicated AIS antenna is beneficial and when a shared VHF antenna is the better choice. Do I Need a Separate AIS Antenna?
AIS Antenna for Boats – Complete Marine Installation Guide
AIS antenna for boats selection is not always about buying a dedicated AIS-only antenna. In many marine installations, a suitable marine VHF antenna can also be used for AIS, provided it covers the correct frequency range, is installed correctly, and is connected with suitable marine-grade cable.
This guide explains how AIS antennas work, when a standard marine VHF antenna can be used, whether you need a separate antenna or AIS splitter, and how mounting position affects real-world AIS performance on yachts, workboats, commercial vessels and leisure craft.
AIS Antenna for Boats: What Does It Do?
An AIS antenna allows an AIS transceiver or receiver to transmit and receive Automatic Identification System signals. AIS is used to exchange vessel information such as position, speed, heading and identity with nearby vessels, shore stations and compatible chartplotters.
AIS operates close to the upper end of the marine VHF band, using AIS frequencies around 161.975 MHz and 162.025 MHz. Because of this, many good-quality marine VHF antennas are suitable for AIS use, as long as their frequency coverage includes the AIS channels.
Can a Marine VHF Antenna Be Used for AIS?
Yes, in many cases a marine VHF antenna can be used for AIS. The key point is whether the antenna covers the standard marine VHF band and extends high enough to include AIS frequencies.
This is important because many customers search for an “AIS antenna” expecting a completely different product, when in practice the correct solution may be a broadband marine VHF antenna, a dedicated second antenna, or an AIS splitter depending on the installation.
At F&C Marine, suitable options include selected AC Antennas and Comar antennas that are chosen for marine communications systems, including AIS-capable installations. AC Antennas are commonly used across both commercial and leisure marine installations where reliable communications performance and durable construction are important.
View our range of AIS antennas and compatible marine VHF antennas.
AIS Antenna vs AIS Splitter
There are two common ways to connect an AIS system to an antenna:
- Dedicated AIS antenna – a separate antenna connected directly to the AIS transceiver or receiver.
- AIS splitter – a device that allows one suitable VHF antenna to be shared between the VHF radio and AIS system.
A dedicated AIS antenna gives separation between systems and can be a strong choice where there is enough mounting space. This is often preferred on larger vessels, commercial craft, or installations where system independence is important.
An AIS splitter is useful where masthead space is limited or where the existing VHF antenna is already installed in the best position. Splitters are common on yachts and smaller vessels where fitting a second antenna may be difficult.
View our range of AIS splitters and AIS transceivers.
Where to Mount an AIS Antenna
AIS performance depends heavily on antenna position. Height, separation, cable quality and clear line of sight all affect range and reliability.
For best results, the antenna should usually be mounted as high as practical, with a clear view around the vessel. On yachts, masthead mounting can provide excellent range, although cable length and cable loss must be considered. On powerboats and commercial vessels, wheelhouse roof, rail, arch or dedicated antenna mast positions are common.
Where a separate AIS antenna is fitted near a VHF antenna, allow suitable separation where possible to reduce interaction between antennas. Avoid mounting the antenna where it is blocked by metalwork, radar scanners, masts, superstructure or other equipment.
See our range of marine antenna mounts and fittings for mast, rail and deck installations.
Choosing the Right AIS Antenna for Boats
The best AIS antenna setup depends on the vessel and installation.
Small Boats and RIBs
Compact antenna options or a splitter may be preferred where space is limited. Cable runs are usually shorter, but the antenna still needs a clear mounting position.
Sailboats and Yachts
Masthead antennas give strong range, but cable quality becomes very important because long cable runs can reduce signal performance. A splitter may be useful where the masthead VHF antenna is already installed.
Commercial Vessels and Workboats
Commercial installations often benefit from robust antenna construction, reliable mounting hardware and professional-grade cable. AC Antennas products are commonly selected where durable marine communications performance is required.
Mixed Marine Electronics Installations
Where AIS, VHF, GPS, NMEA 2000 and chartplotter systems are installed together, antenna planning should be considered as part of the whole communications system rather than as a single standalone item.
Common AIS Installation Mistakes
- Using an antenna that does not properly cover AIS frequencies – always check frequency suitability.
- Mounting the antenna too low – AIS range depends strongly on antenna height and line of sight.
- Using poor-quality coaxial cable – cable loss can reduce performance, especially on longer runs.
- Ignoring antenna separation – poor spacing can affect system performance.
- Choosing a splitter without considering the full system – VHF radio, AIS transceiver and antenna compatibility should all be checked.
- Poor connector installation – badly fitted coax connectors are a common cause of unreliable marine communications.
View our marine cable assemblies for AIS and VHF antenna installations.
Recommended AIS Antennas and Accessories
F&C Marine supplies AIS-capable marine antenna solutions, including AC Antennas, Comar antennas, AIS splitters, marine VHF antennas, coaxial cable, connectors and mounting accessories for professional and leisure marine installations.
- AIS antennas and marine VHF antennas
- AIS splitters
- AIS transceivers
- Marine cable assemblies
- Marine antenna mounts and fittings
Need Help Choosing the Right AIS Antenna Setup?
Choosing the correct AIS antenna for boats depends on antenna location, cable quality, vessel type and whether the system uses a dedicated antenna or AIS splitter.
If you are unsure whether your vessel needs a dedicated AIS antenna, an AIS splitter, or a shared marine VHF antenna system, contact F&C Marine for practical guidance based on your vessel type, mounting position and onboard electronics.
Shop AIS antennas and accessories
For further technical information about AIS systems and marine radio communications, see the International Telecommunication Union (ITU).