Vision is the result of the reflection of light waves from the objects around us. These invisible waves collide with the object, person or things, reach our eyes and as a result we can see the things around us. Using the same principle RADAR works. RADAR which stands for radio detection and ranging, which actually works on the radio waves present around us, helps us in tracking, monitoring and controlling traffic both in air and ground. It is most helpful in the cases like
- To detect the speed of an object which is most helpful in monitoring and controlling traffic
- To detect the presence of an object at a distance and tracing it.
- Helps in mapping the space shuttle and orbiting satellites.
The above can be achieved using the basic three components, transmitter or generator to generate waves, receiver to receive them and something for the means of displaying information. Radar works on principle of echo and Doppler shift.
The following steps explain how Radar works
- Magnetron which is responsible for generation of radio waves in radar. It generates high frequency radio waves.
- Duplexer switches magnetron to swap back and forth to antenna.
- Once the radio waves have been generated, an antenna, working as a transmitter sends narrow beam of radio waves through the air.
- Radio waves hit any object and reflect back.
- Antenna acts as both transmitter and receiver, alternately sending out radio waves and receiving them. While the antenna is transmitting, it cannot receive and vice-versa. When the waves reflect back antenna picks up reflected waves during a break between transmissions.
- Duplexer switches antenna through a receiver unit.
- Computer in receiver unit processes reflected waves and draws them on a TV or the monitor screen.
- Any plane or object shows up on TV radar display with any other nearby targets.