When was radar created

Soon Watson-Watt was using pulsed radio waves to detect airplanes up to 80 miles away. These stations, known as Chain Home, successfully alerted the Royal Air Force to approaching enemy bombers, and helped defend Britain against the German Luftwaffe in the Battle of Britain.

The Chain Home system worked fairly well, but it required huge antennas, and used long wavelengths that limited ability to pinpoint enemy aircraft accurately. During the day, fighter pilots could see enemy bombers. But soon the Germans began nighttime bombing missions, so to help fighter pilots locate enemy aircraft at night, the British needed a shorter wavelength radar system that was compact enough to install in planes.

This became possible when British engineers Harry Boot and John Randall invented the cavity magnetron in early The magnetron generated about hundred watts of power at wavelengths about 10 centimeters, enough to produce echoes from airplanes many miles away. The MIT Radiation Laboratory, was set up and quickly became one of the largest wartime projects, employing about people. Researchers and workers there made mass-production versions of the magnetron and developed about different radar systems.

After the war, many peaceful uses for radar technology were found. Today air traffic control depends on radar to keep commercial aircraft from colliding. Radar is essential for tracking the weather. The cavity magnetron is now used to cook food in microwave ovens. And many motorists have been caught speeding by police radar guns, including, reportedly, Sir Watson-Watt himself. Impressed, the air ministers embraced the new technology and by September , when war broke out in Europe, the British had a network of radar installations covering the English Channel and North Sea coasts.

It was radar, even more than the pluck of the dashing RAF pilots, that tipped the scales in England's favor in the Battle of Britain. Hitler's strategic aerial onslaught, meant to clear the skies over the Channel and southeastern England preparatory to an invasion of the British Isles, might have succeeded if not for radar. The RAF was outnumbered by the Luftwaffe, and radar saved already-stretched Fighter Command from having to maintain constant air surveillance.

With radar providing an early-warning system, well-rested RAF pilots could be scrambled and rising to meet the incoming enemy formations in a matter of minutes.

Within the framework of his experiments he used special reflectors. While experimenting with Hertz's reflector, he noticed that electric waves that were emitted from a transmitter and reflected by a metal surface can be used to detect distant metallic objects. He then developed a device that could measure the transit time of reflected waves: the telemobiloscope. On 30 April , he took out a patent for the process and is therefore the inventor of radar.

Another important discovery during the development of radar was the verification of the Doppler effect.