1934, Peggy, an American scientist, first observed the radio waves (referred to as echoes) reflected by airplanes 1.6 kilometers away. 1935 February, British scientist Watt and his assistant, in an experiment, suddenly found an unusual phenomenon on the "echo display"-not a white dot, but a short line. Watt exclaimed, "Three planes!" It was later confirmed that three planes did fly there at that time. Watt therefore designed the original radar, which was then called a radio scout. With the support of the British government, this kind of radar has been popularized and a combat "radar network" has been established in Britain.
Radar played a great role in the Second World War.
In the famous "Great Britain War", German fascists dispatched thousands of bombers and fighter planes to bomb Britain on a large scale. However, whether it is an invasion during the day or a sneak attack at night, German planes will always suffer heavy losses in thrilling air battles.
Why can British fighters, who are at a disadvantage in number, win in the face of the dense fleet of German aircraft? The book The Great Battle of World War II has been analyzed. In addition to the fact that the Germans underestimated the strength of the Royal Air Force, there is another important reason, that is, Marshal Goering of the German Air Force did not know and did not expect the existence of the British "radar network".
At that time, Britain set up a series of secret radar stations on the south coast of England and as far as the east coast of Scotland.
These radars include air defense early warning radar, ground guidance radar, searchlight radar and anti-aircraft gun radar. Dozens of air defense early warning radars launch radio beams into the air day and night, constantly scanning enemy planes, just like the "encirclement" in fairy tales. As soon as the German plane broke into the "net" of radar beams, the radio waves reflected and produced echoes. As soon as the echo appears on the display, the azimuth, distance, batch and altitude of the aircraft can be quickly measured, creating favorable conditions for annihilating enemy planes.
The "radar network" of many radars is very strict. In order to make up for the "loophole" at low altitude (the "blind area" of general radar), several radars should be set up at a very high place to scan the emitted radar beams at low altitude. At that time, the ground-based radar was able to detect enemy planes 80 kilometers away, accurately guide their own planes into the most favorable interception airspace, and command and kill enemy planes. The interception radar on the plane can quickly find and aim at enemy planes even in the dark and gunfire. In a night air battle, a British fighter plane shot down six German planes in succession. Searchlight radar can improve the aiming rate of searchlights by more than 10 times. Anti-aircraft gun radar can make anti-aircraft gun automatically track, aim and shoot. It was precisely because there were so many "clairvoyance" in Britain at that time to monitor the invading German planes, so although German planes were superior in number, they often suffered defeat.
Up to now, the deployment of radar in war is more intensive. In some important areas, when the invading plane is over 300 meters, there may be 800 ~ 900 radars around to monitor it. Among them, there may be 300 ~ 400 radars that will search for it with about 600 ~ 700 electric beams with different frequencies. In addition, it is more dangerous that 30 ~ 40 radars may have tracked them at close range with 40 ~ 50 radio beams of different frequencies, or searched them through sector scanning. In other words, the invading plane is in public danger at this time. Because, since the appearance of missiles, once the plane is discovered, it means that it will be destroyed, and some missiles are almost a hundred shots.