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1 antena ultrakrótkofalowa
• ultra-high-frequency antennaSłownik polsko-angielski dla inżynierów > antena ultrakrótkofalowa
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2 Yagi, Hidetsugu
[br]b. 28 January 1886 Osaka, Japand. January 1976 Osaka, Japan[br]Japanese engineer who, with his student Shintaro Uda, developed the directional ultra-high frequency (UHF) aerial array that bears his name.[br]Yagi studied engineering at Tokyo Imperial University (now Tokyo University), graduating in 1910. For the next four years he taught at Engineering High School in Sendai, Honshu, then in 1914 he was sent to study resonance phenomena under Barkhausen at Dresden University. When the First World War broke out he was touring Europe, so he travelled to London to study under Ambrose Fleming at University College, London. Continuing his travels, he then visited the USA, studying at Harvard under G.W. Pierce, before returning to his teaching post at Sendai Engineering High School, which in 1919 was absorbed into Tohoku University. There, in 1921, he obtained his doctorate, and some years later he was appointed Professor of Electrical Engineering. Having heard of the invention of the magnetron, he worked with a student, Kinjiro Okabe; in 1927 they produced microwave energy at a wavelength of a few tens of centimetres. However, he is best known for his development with another student, Shintaro Uda, of a directional, multi-element ultrahigh frequency aerial, which he demonstrated during a tour of the USA in 1928. During the Second World War Yagi worked on radar systems. After his retirement he became Professor Emeritus at Tohoku and Osaka universities and formed the Yagi Antenna Company.[br]Principal Honours and DistinctionsYagi received various honours, including the Japanese Cultural Order of Merit 1976, and the Valdemar Poulsen Gold Medal.Bibliography1928, "Beam transmission of ultra-short waves", Proceedings of the Institute of Radio Engineers 6:715 (describes the Yagi-Uda aerial).Further ReadingF.E.Terman, 1943, Radio Engineers' Handbook, New York: McGraw-Hill (provides a review of aerials, including the Yagi system).KF -
3 частота оптического диапазона
Русско-английский словарь по информационным технологиям > частота оптического диапазона
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