Updated: 26 October 2026 · 3 min read
AIS AtoN uses the Automatic Identification System to broadcast information about an aid to navigation, so that buoys, lights and platforms appear as symbols on the ECDIS and radar of every ship in range, with name, position and status.
How it works
AIS exchanges digital messages on the two maritime VHF AIS channels (161.975 MHz and 162.025 MHz) following ITU-R M.1371. AtoN use Message 21 – Aids-to-Navigation report, which carries the AtoN MMSI (99MIDxxxx format), name, type, position, dimensions, an off-position flag, status and a real/virtual flag.
Three kinds of AIS AtoN
| Kind | Physical AtoN | Transmitted from | Typical use |
|---|---|---|---|
| Real | Yes | AIS unit on the AtoN itself | Fairway buoys, lighthouses, platforms |
| Synthetic | Yes | Shore station on its behalf | AtoN that cannot host AIS hardware; monitored or predicted |
| Virtual | No | Shore station | New wrecks, temporary exclusion zones, pipelines |
A virtual AIS AtoN can mark a new hazard within minutes, whereas laying a physical buoy needs a work boat and a weather window.
Station types
IEC 62320-2 covers AIS AtoN stations, commonly grouped as Type 1 (transmit only, configured locally), Type 2 (transmit and receive, remotely configurable over AIS) and Type 3 (Type 2 plus full receive capability for advanced monitoring and data sharing). The choice depends on available power, remote configuration needs and monitoring requirements.
Monitoring over AIS
AIS AtoN stations can also send Application Specific Messages (ASM) in Messages 6 or 8 with monitoring data – battery voltage, solar charge current, main/standby lamp status, racon status, door or impact sensors. No airtime cost, but coverage is limited to shore station VHF range and the traffic adds load to AIS – one reason the industry is moving to the dedicated ASM channels of VDES.
Deployment tips
- Register an AtoN MMSI with the national authorities before transmitting.
- Align names and types with Notices to Mariners and charts.
- Set reporting intervals that do not overload AIS in busy ports.
- Publish virtual AtoN through a formal approval and notice process.
- Use 4G or satellite monitoring for AtoN beyond shore station range.
Phuc Nguyen Marine supplies AIS AtoN equipment and racons and integrates AIS data into its remote monitoring platform. See products.
References: ITU-R M.1371; IEC 62320-2; IALA R0126; iala.int.