Racons

Racons are radar beacons, navigational aids that respond to a radar interrogation with a distinctive identifying signal. They are designed to enhance a ship’s ability to identify fixed objects such as buoys, lighthouses, wrecks, and obstructions on the radar display, particularly in low-visibility conditions.

Operation: A racon is a small transponder installed on a navigational mark. When illuminated by a ship’s radar, it replies with a coded pulse sequence that, on the radar screen, appears as a Morse code pattern corresponding to the station’s identity. The resulting symbol helps mariners confirm the mark’s position and identity.

Deployment: Racons are mounted on buoys, lighthouses, harbour entrances, dredged channels, and wrecks. They are tuned to operate with radar wavelengths used by ships, often in the X-band, and are powered by on-site electrical supply or solar panels.

Standards and identification: International guidelines, published by the IALA and related national authorities, govern the use and marking of racons. The radar presentation displays the racon’s Morse code pattern, which is unique to each installation and helps distinguish it from other targets.

Benefits and limitations: Racons improve situational awareness by providing instantaneous radar identification, reducing ambiguity in complex waterways. They require radar interrogation to be observed, are dependent on power and maintenance, and may be affected by environmental conditions, radar performance, or interference. They do not replace other navigational aids and are used in conjunction with lights, buoys, and chart information.