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In the summer of 1940, the Tizard Mission visited the United States. Īfter the Fall of France, it was realised in Great Britain that the manufacturing capabilities of the United States were vital to success in the war thus, although America was not yet a belligerent, Prime Minister Winston Churchill directed that the technological secrets of Great Britain be shared in exchange for the needed capabilities. In February 1940, Great Britain developed the resonant-cavity magnetron, capable of producing microwave power in the kilowatt range, opening the path to second-generation radar systems. While the benefits of operating in the microwave portion of the radio spectrum were known, transmitters for generating microwave signals of sufficient power were unavailable thus, all early radar systems operated at lower frequencies (e.g., HF or VHF). Navy in 1940, and the term "radar" became widely used. The acronym RADAR (for Radio Detection And Ranging) was coined by the U.S. Navy in early 1940, and a year later by the U.S. The first of these were fielded by the U.S. recognized the potential of the new technology, and began development of ship- and land-based systems.
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In the United States, the technology was demonstrated during December 1934, although it was only when war became likely that the U.S. In Great Britain, it was called RDF, Range and Direction Finding, while in Germany the name Funkmeß (radio-measuring) was used, with apparatuses called Funkmessgerät (radio measuring device).īy the time of the Battle of Britain in mid-1940, the Royal Air Force (RAF) had fully integrated RDF as part of the national air defence. At the outbreak of war in September 1939, both Great Britain and Germany had functioning radar systems.
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This revolutionary new technology of radio-based detection and tracking was used by both the Allies and Axis powers in World War II, which had evolved independently in a number of nations during the mid 1930s. Radar in World War II greatly influenced many important aspects of the conflict.
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