Early history of polish radars

The history described in this article starts in the 1920s, when one of the founders of Polish radiolocation, Professor Janusz Groszkowski from the Warsaw University of Technology, started his research in radio-communications technology. Professor Groszkowski received his PhD in 1928 for his work entitled "The Compensation Method for Controlling Wave Stability" [1]. He had already published a revolutionary discussion in Polish in 1925 on "Cathode Waves and Their Use in Radiotelegraphy", which has since been translated into many languages; the first translation, entitled "Les Lampes a plusieures electrodes et leurs applications en radiotechnique", was published in Paris in 1927. In the 1930s, he continued his research in this area, and in 1935 he established the State Telecommunications Institute in Poland, now known as PIT (the present name is PIT-RADWAR). Since then, tremendous progress in Poland in the development of applied technology in radio-communications has been observed. Many intentioned technologies invented by Professor Groszkowski were later applied in radars, the main two being the first oxide-coated cathode applied in magnetron (1937) [8] and the first metal magnetron with inner resonant circuits and an oxide cathode (1939) [9].