Radar Transponder (RACON)
A Racon is a type of radar transponder commonly used to mark maritime navigational hazards. The word is an acronym for RAdar beaCON.
Racons are receiver/transmitter devices operating in the maritime radar frequency bands (9 and 3 GHz) that enhance the detection and identification of certain radar targets. A Racon responds to the presence of a ship’s radar by sending a characteristic pulse train. The response appears as a coded mark (or “paint”) on the ship’s radar display that highlights the range and bearing of the racon. The displayed paint has a length on the display corresponding to a few nautical miles and uses a Morse character for identification. When a racon receives a radar pulse, it responds with a signal on the same frequency which leaves an image on the radar display. This takes the form of a short line of dots and dashes forming a Morse character radiating away from the location of the beacon on the normal plan position indicator radar display.
A racon is generally considered to be a supplementary aid to navigation installed at sites that would also be marked with a light. As noted in the IMO carriage requirements contained in Chapter V of the SOLAS Convention,1974, a large number of vessels are capable of making use of a racon. Racons used for purposes other than aids to navigation is prohibited, and they are used to mark:
- lighthouses and navigation buoys
- offshore wind farms
- positions on inconspicuous coastlines
- offshore oil platforms and other structures
- environmentally-sensitive areas such as coral reefs
- ranging and identification of locations on inconspicuous coastlines
- marking hazards
- indicating navigable spans under bridges
- as a leading line
Their characteristics are defined in the publication: ITU-R Recommendation M.824, Technical Parameters of Radar Beacons (RACONS).
General RACON information
There are two different operating modes:
- The frequency-agile racon which represents current technology, and;
- The original and largely obsolete swept-frequency racon.
Frequency-Agile Racon: Responds on the frequency on which they are interrogated and hence the response could be re-painted on each radar sweep.
However, to avoid masking other features on the radar screen the racon response is usually switched on and off on a preset cycle.
Table 3.9 Preferred terminology for the description of racon operating frequencies.
Preferred Terminology Alternatives
9 GHz 9300 -9500 MHz X - band 3 cm
3 GHz 2900 -3100 MHz S - band 10 cm
Get a call or get an email with further details on our products.
Get data sheet
Get an overview of the technical data, applications and design.
Sign up for newsletter
Did you find what you were looking for?
Help us make the product pages even better.