Principle of Radar
Radar works on the principle of 'radio echoes'. The transmitter in a radar, radiates the high power electrical pulses into space. When these pulses are incident on any distant target such as a mountain, ship or aircraft, they get scattered in all directions. The transmitter antenna receives a part of the scattered energy. This transmitter antenna also acts as receiving antenna for receiving pulse. The pulse travels with the speed of light 3*108 ms-1.In other words, these pulse cover a distance of 300 meters for every micro second. hence by measuring the time taken by the pulse to reach the target and back to the transmitter, the range or distance of the target can be easily determined. To locate the direction of the target, directional antennas are used.