Leonard Stanisław Danilewicz was a Poland engineer and, for some ten years before the outbreak of World War II one of the four directors of the AVA Radio Company in Warsaw Poland. AVA designed and built radio equipment for the Polish General Staff s Biuro Szyfrów which was responsible for the radio communications of the General Staffs Oddział II(Section II, the General Staffs military intelligence section).Władysław Kozaczuk Enigma: How the German Machine Cipher Was Broken, and How It Was Read by the Allies in World War Two 1984, p. 27. Beginning in 1933, after the Cipher Bureaus mathematician cryptologist Marian Rejewski reconstructed the Germany military Enigma machine rotor cipher machine AVA built Enigma "doubles" as well as all the electro-mechanical equipment subsequently designed at the Cipher Bureau to expedite routine breaking and reading of Enigma ciphers.Władysław Kozaczuk Enigma: How the German Machine Cipher Was Broken, and How It Was Read by the Allies in World War Two 1984, pp. 26–28 and passim AVAs other directors were Edward Fokczyński Antoni Palluth and Leonard Danilewiczs elder brother, Ludomir Danilewicz The company took its name from the combined radio callsign of the Danilewicz brothers (TPAV and Palluth (TPVA. When the company was being formed about 1929, the Danilewicz brothers were short-wave "amateur radio operator " and students at the Warsaw Polytechnic Władysław Kozaczuk Enigma 1984, p. 26. Leonard Danilewicz early showed remarkable creativity as a radio designer, coming up with a concept for spread spectrum#Frequency hopping

See also

*AVA Radio Company *Spread spectrum#Frequency hopping *Frequency-hopping spread spectrum#Multiple inventors of frequency hopping concepts *[[Biuro Szyfrów]](Cipher Bureau) *Marian Rejewski *Enigma machine *Cryptanalysis of the Enigma *Ultra *Lacida

Notes

References

*Władysław Kozaczuk Enigma: How the German Machine Cipher Was Broken, and How It Was Read by the Allies in World War Two edited and translated by Christopher Kasparek Frederick, MD, University Publications of America, 1984, ISBN 0-89093-547-5.

External links

* Laurence Peter, http://news.bbc.co.uk/2/hi/europe/8158782.stm How Poles cracked Nazi Enigma secret], BBC News, 20 July 2009 Category:Polish engineers