in navigation, an electric beacon (or electromagnetic beacon) is a kind of beacon, as a device which sends a signal and marks a fixed location and allows direction finding equipment to find relative bearing, as the direction to the beacon. the most common are radio beacons, which broadcast a radio signal which is picked up by radio direction finding systems on ships, aircraft or cars to determine the bearing to the beacon. however, the term "beacon" also covers infrared and sonar beacons.