• A Radar beacon is a small radar set consisting of a receiver, a separate transmitter and an antenna which is often omnidirectional.
  • When another radar transmits a coded set of pulses at the beacon i.e it interrogates it, the beacon responds by sending back its specific pulse code.
  • The pulse from the beacon or transponder may be at the same frequency as those from the interrogating radar, in which case they are received by the main station together with its echo pulses.
  • They may alternatively be at a special beacon frequency, where a separate receiver is required by the interrogating radar.
  • The beacons does not transmit pulses continuously in the same way as a search or tracking radar but only to the correct interrogation.

Radar beacons are used as:

• One of the application of a beacon may be to identify itself. The beacon may be installed on a target (aircraft) and will transmit a specific pulse code when interrogated these pulses then appear on the PPI of the interrogating radar and inform it of the identity of the target. The system is used in airport traffic control and also for military purpose, where it is called identification, friend or foe (IFF).
• Another use is similar to that of lighthouses, except that radar beacons can operate over much larger distances.