How does an aircraft radar work and what is its importance?

Radar (an acronym for Radio Detection And Ranging) is a device that is used extensively on aircraft. It works on echo principle. Just like other radar systems, aircraft radar also contains high frequency radio waves that are transmitted for a short time phase during which the waves reach the highest altitude. When any kind of solid obstruction comes in the path of the transmitted waves, it strikes the object and gets reflected back to the radar, helping the object's detection along with its exact distance from the radar.

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