Radar is a typical example of a technology that developed significantly later than the original physics behind it."
—Institute of Physics
Radar is a system of detection used to identify the location, velocity, and angle of objects. It utilizes the Doppler Effect, which is the change of a wave's frequency for an observer relative to its source. Radar involvers a transmitter emitting radio waves or microwaves, which bounce off of objects and return a frequency to the transmitter. Through use of several of these stations, the location and other properties of objects can be located.
The Doppler Effect
The Doppler Effect can be easily described visually as the ripples in the water as a swan moves in it. If the water is the transmission system, the swan is the object emitting these waves. The ripples in front of the swan, being recorded by the water, are "squished" in comparison to the waves behind it, which are extended.
A Breif History of Radar 1888
Heinrich Hertz is first to send and receive radio waves 1935
Robert Watson-Wyatt uses radio waves to detect aircraft during World War II 1957
Positioning of Sputnik 1 detected by William Guier and George Weiffenbach 1970s Radar became standardized and organized into networks for weather. 1983
Shooting down of Korean Air Lines Flight 007 by Soviet prompts Reagan administration to release information and future civilian access to the GPS system
The first applications of radar were in World War II, where similar technologies were evolved at the same time to detect the location of war vehicles, beginning with Robert Watson-Wyatt in England. Throughout the Cold War, long-range detection systems were developed from both sides, used to track movements of missiles. This resulted in large structures for detection being built and intercepting radio stations around the world with their emittances, sparking conspiracy theories about the meanings of these radio waves. As technology advanced, homing beacons were disguised as everyday objects to pinpoint military locations during the Vietnam war.
THE RUSSIAN WOODPECKER
Starting in 1976 a new and powerful radio signal was detected worldwide, interfering with all types of stations, and quickly dubbed the Woodpecker by amateur radio operators. This gave rise to theories of Soviet mind control and weather control experiments. However, many experts and amateur radio hobbyists quickly realized it to be an over-the-horizon radar system.
While a developed version of this technology is now used in military in its GPS form, it has also been widely applied to meteorology, transport, astronomy, and geophysical mapping. In 1946, the moon was detected using radar. Since the 1970s, radio waves have become standardized in weather detection. Although its principles are simple, has become a powerful tool in both peace and war.