Radar Principles

Advances in radar system hardware and software have enabled radar systems to detect, differentiate, classify, image, and track the range, altitude, direction, or velocity of multiple moving or fixed targets simultaneously. A radar system has a receiver intended to detect the reflected electromagnetic waves, indicating an object with a different dielectric constant in the propagation direction. Doppler radar is typically used to detect moving targets, and estimate their velocity. Security systems motion detectors and door openers are common uses of Doppler radar‐based motion detectors. There are two basic radar configurations based on the spatial relationship between the transmitting and receiving antennas: monostatic and bistatic. The major areas of radar application are briefly described, including military defense and weapons systems, remote monitoring of the Earth's surface, the ocean, and other planets, reconnaissance imaging, ground‐penetrating radar for archeological expeditions, weather surveillance, air traffic control, and others.