Radar configurations and types

Radar configurations and types is an article about listing the different uses of radars.

Radar come in a variety of configuration in the emitter, the receiver, the antenna, wavelength, scan strategies, etc.

Search radars scan a wide area with pulses of short radio waves. They usually scan the area two to four times a minute. The waves are usually less than a meter long. Ships and planes are metal, and reflect radio waves. The radar measures the distance to the reflector by measuring the time of the roundtrip from emission of a pulse to reception, dividing this by two, and then multiplying by the speed of light. To be accepted, the received pulse has to lie within a period of time called the range gate. The radar determines the direction because the short radio waves behave like a search light when emitted from the reflector of the radar set's antenna.

Targeting radars use the same principle but scan a much narrower area far more often, usually several times a second or more, where a search radar might scan more widely and less frequently. Missile lock-on describes the scenario where a targeting radar has acquired a target, and the fire control can calculate a path for the missile to the target; in semi-active radar homing systems, this implies that the missile can "see" the target that the targeting radar is "illuminating". Some targeting radars have a range gate that can track a target, to eliminate clutter and electronic countermeasures.

Radar proximity fuzes are attached to anti-aircraft artillery shells or other explosive devices, and detonate the device when it approaches a large object. They use a small rapidly pulsing omnidirectional radar, usually with a powerful battery that has a long storage life, and a very short operational life. The fuzes used in anti-aircraft artillery have to be mechanically designed to accept fifty thousand g, yet still be cheap enough to throw away.

Weather radars can resemble search radars. This radar uses radio waves along with horizontal, dual (horizontal and vertical), or circular polarization. The frequency selection of weather radar is a performance compromise between precipitation reflectivity and attenuation due to atmospheric water vapor. Some weather radars uses doppler shift to measure wind speeds and dual-polarization for identification of types of precipitations.

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