Radar: In basic communications, there are two types of communication one is analog and another is digital. But in advanced communication, we will discuss the communication through radar, satellite etc. Mostly they are developed for of military purpose or security purpose. A radar consists of a transmitter and receiver, each connected to a directional antenna. The transmitter radiates or transmits electromagnetic radiations generated by a magnetron oscillator. The receiver antenna, collects the returned echo signal and delivers it to the receiver where it is processed to detect the presence of the target and to extract its relative velocity with respect to radar station if the target is moving.
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