We must have seen planes, ships, missiles. But radar does the work of giving it the right direction and identifying it. Like land, it serves the same function from sea to space. The full name of radar is Radio Detection And Ranging. Radar was invented by Taylor and Leo Ying in 1922. But its real form came before the world during the Second World War.
The first practical radar was developed in 1935 by the British physicist Robert Watson Watt, then in 1939 England established a radar station on the coast to detect and avoid enemy attacks in the air and at sea. In India mainly radars are manufactured by DRDO.
A radar behaves like a radio station and the waves it emits are called radio waves. The speed of such waves is equal to the speed of light. Radar is not affected by rain, storm, cloudy weather. Radar can monitor the movements in the air and at sea.
The work of radar is based on a reflection, like if we shout in an open space, we hear our voice back in the form of an echo. Similarly, any type of radar has one or more transmitters or receivers. The waves sent by the radar are moving through the transmitter. This transmitter keeps sending the waves but if any craft or object comes in between such waves, the waves are broken immediately and such waves which hit the object and bounce back so it is received by the receiver. By receiving it, it gets information about the height, distance and speed of the craft or object.
Radar is also called a subtle eye which can easily identify a distant object but it does not get small information like the color composition of an object but it only gives an impression of a figure. When the receiver tracks an object, then it is only seen as a dot on its screen. As the object approaches the radar, the dot becomes denser and gives information to the control unit.
Earlier radars were very large and bulky, in the modern era, cavity magnetrons are used to make them smaller in size and with longer ranges. On January 19, 1946, the US Army Signal Force contacted the moon with the help of radar. The signal sent traveled four and a half million miles, which was the longest signal in history. It took only two and a half seconds to reach.
Even in space, radio waves are sent from the earth by radar to know the distance of any planets, satellites, or a large meteorite. These waves collide with the planets and come back, and by calculating with time, the distance to the planets can be known.
As time goes by, stealth technology is used in aircrafts used by the military to avoid contact with the enemy country. In it, any aircraft or ship is painted with a special metal. It absorbs radio waves so the radio waves are not reflected back to earth, causing stealth planes and ships to disappear from radar.
But such craft are barely visible to the naked eye because their speed and capacity are low and they cannot fly at high altitudes. Especially because of radar, the country's military is strengthened and also protected from surprise attacks as the incoming ships and rockets are already alerted.
Initially, radar was used only for military purposes but now it is used for air transport, maritime transport, communication in space, mountain height, direction, distances, and weather forecasting.
-- Bhautik Thummar.
