RADAR stands for RAdio Detecting And Ranging and as indicated by the name. It refers to an electronic equipment that detects the presence of objects by using reflected electromagnetic energy. Under some conditions a radar system can measure the direction, height, distance, course and speed of these objects.

    Radars send out electromagnetic waves similar to wireless computer networks and mobile phones. The signals are sent out as short pulses which may be reflected by objects in their path. Only small portion of the reflected energy returns to the radar set. This returned energy is called an ECHO, just as it is in sound terminology. Radar sets use the echo to determine the direction and distance of the reflecting object. The frequency of electromagnetic energy used for radar is unaffected by darkness and also penetrates fog and clouds. This permits radar systems to determine the position of airplanes, ships, or other obstacles that are invisible to the naked eye because of distance, darkness, or weather.


    Components of RADAR

    Transmitter: The radar transmitter produces the short duration high-power RF-pulses of energy that are into space by the antenna.

    Duplexer: The Duplexer module acts as a switch to toggle the antenna between sending & receiving modes. This switching is necessary because the high-power pulses (of the range of  MW) of the transmitter would destroy the receiver (which works on microwatt power) if energy were allowed to enter the receiver.

    Receiver: The receivers amplify and demodulate the received RF-signals. The receiver provides video signals on the output.

    Radar Antenna: The Antenna transfers the transmitter energy to signals in space with the required distribution and efficiency. This process is applied in an identical way on reception.

    Indicator or display: The indicator should present to the observer a continuous, easily understandable, graphic picture of the relative position of radar targets.


    How RADAR Work ?

    The radar employs a magnetron to generate radio waves characterized by longer wavelengths and higher frequencies. These waves are capable of travelling a long distance without attenuation.

    Once the radio waves are generated and are transmitted using radar antenna, they keep travelling until they encounter an obstruction/object of any nature. On contact with an obstruction/object, some of the waves reflect back to the radar. An antenna is usually curved so it focuses only on a narrow beam, but a radar antenna usually rotates so that it can track movements over a large area.

    The reflected waves received by same radar antenna are directed to receiver which processes and converts them into a video format and then displays on the output system for an operator to understand.