• A system or technique in which microwave radiation is beamed by a transmitter, and the radiation reflected off objects is detected and analyzed to indicate the presence of said objects. A radar may also be able to provide information on the range, bearing, speed, altitude, and other characteristics of one or more scanned objects. Radars can emit the microwave energy in pulses, or in a continuous manner. In an active radar, which is the norm, microwaves are transmitted to enhance the detection of scanned objects, while a passive radar detects the microwave energy which is ordinarily radiated and reflected from any given object. A Doppler radar employs the Doppler effect to determine the velocity of a scanned object. There may also be multiple sets of transmitters and receivers, as in frequency-diversity radar. Used, for instance, to track and guide aircraft and ships, or to monitor weather conditions.
  • An apparatus utilized to generate, transmit, receive, and display information utilizing radar (1). A typical set has a source of microwave power, such as a magnetron, transmitting and receiving antennas, a receiver, and a display, such as a CRT or LCD. Also called radar system, radar unit, radar set, radar apparatus, radar equipment, or radar installation.
  • synonymradio detection and ranging


  • noun a system for detecting aircraft, vehicles, ships or other objects, through the transmission of high-frequency electromagnetic waves which are reflected back by the object

General Science

  • abbreviation forradio detection and ranging