Frequency-hopping
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Frequency-hopping
Frequency-hopping spread spectrum (FHSS) is a method of transmitting radio signals by rapidly changing the carrier frequency among many distinct frequencies occupying a large spectral band. The changes are controlled by a code known to both transmitter and receiver. FHSS is used to avoid interference, to prevent eavesdropping, and to enable code-division multiple access (CDMA) communications. The available frequency band is divided into smaller sub-bands. Signals rapidly change ("hop") their carrier frequencies among the center frequencies of these sub-bands in a predetermined order. Interference at a specific frequency will affect the signal only during a short interval. FHSS offers four main advantages over a fixed-frequency transmission: # FHSS signals are highly resistant to narrowband interference because the signal hops to a different frequency band. # Signals are difficult to intercept if the frequency-hopping pattern is not known. # Jamming is also difficult if the p ...
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Transmitter
In electronics and telecommunications, a radio transmitter or just transmitter is an electronic device which produces radio waves with an antenna. The transmitter itself generates a radio frequency alternating current, which is applied to the antenna. When excited by this alternating current, the antenna radiates radio waves. Transmitters are necessary component parts of all electronic devices that communicate by radio, such as radio and television broadcasting stations, cell phones, walkie-talkies, wireless computer networks, Bluetooth enabled devices, garage door openers, two-way radios in aircraft, ships, spacecraft, radar sets and navigational beacons. The term ''transmitter'' is usually limited to equipment that generates radio waves for communication purposes; or radiolocation, such as radar and navigational transmitters. Generators of radio waves for heating or industrial purposes, such as microwave ovens or diathermy equipment, are not usually called transmi ...
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Guglielmo Marconi
Guglielmo Giovanni Maria Marconi, 1st Marquis of Marconi (; 25 April 187420 July 1937) was an Italian inventor and electrical engineer, known for his creation of a practical radio wave-based wireless telegraph system. This led to Marconi being credited as the inventor of radio, and he shared the 1909 Nobel Prize in Physics with Karl Ferdinand Braun "in recognition of their contributions to the development of wireless telegraphy".Guglielmo Marconi: The Nobel Prize in Physics 1909
. nobelprize.org
Marconi was also an entrepreneur, businessman, and founder of The Wireless Telegraph & Signal Company in the

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US Army Signal Corps
The United States Army Signal Corps (USASC) is a branch of the United States Army that creates and manages communications and information systems for the command and control of combined arms forces. It was established in 1860, the brainchild of Major (United States)#American Civil War, Major Albert J. Myer, and had an important role in the American Civil War. Over its history, it had the initial responsibility for portfolios and new technologies that were eventually transferred to other U.S. government entities. Such responsibilities included Defense Intelligence Agency, military intelligence, National Weather Service#History, weather forecasting, and Aeronautical Division, U.S. Signal Corps, aviation. Mission statement Support for the command and control of combined arms forces. Signal support includes network operations (information assurance, information dissemination management, and network management) and management of the electromagnetic spectrum. Signal support encompasses a ...
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World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great powers—forming two opposing military alliances: the Allies of World War II, Allies and the Axis powers. World War II was a total war that directly involved more than 100 million Military personnel, personnel from more than 30 countries. The major participants in the war threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. Air warfare of World War II, Aircraft played a major role in the conflict, enabling the strategic bombing of population centres and deploying the Atomic bombings of Hiroshima and Nagasaki, only two nuclear weapons ever used in war. World War II was by far the List of wars by death toll, deadliest conflict in hu ...
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Władysław Kozaczuk
Władysław Kozaczuk (23 December 1923 – 26 September 2003) was a Polish Army colonel and a military and intelligence historian. Life Born in the village of Babiki near Sokółka, Kozaczuk joined the army in 1944, during World War II, at Białystok. In 1945 he became a Polish Army second lieutenant, and spent the first 5 years of his service commanding operational units of the Internal Security Corps, fighting the Polish anticommunist underground and then the Ukrainian Insurgent Army. In 1950 he was transferred to the Internal Security Corps Staff in Warsaw. In 1954–55, following the Korean War, Kozaczuk carried out armistice-related duties in Korea. In 1955–58 he served in the Polish Ministry of Internal Affairs ('). In 1957–58 he saw duty with the International Control Commission in Vietnam. In 1958–69 he served in Polish military counter-intelligence (''Wojskowa Służba Wewnętrzna''). According to his family, he found conditions there uncongenial ...
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Polish Zloty
Polish may refer to: * Anything from or related to Poland, a country in Europe * Polish language * Poles, people from Poland or of Polish descent * Polish chicken * Polish brothers (Mark Polish and Michael Polish, born 1970), American twin screenwriters Polish may refer to: * Polishing, the process of creating a smooth and shiny surface by rubbing or chemical action ** French polishing, polishing wood to a high gloss finish * Nail polish * Shoe polish * Polish (screenwriting), improving a script in smaller ways than in a rewrite See also * * * Polonaise (other) A polonaise ()) is a stately dance of Polish origin or a piece of music for this dance. Polonaise may also refer to: * Polonaises (Chopin), compositions by Frédéric Chopin ** Polonaise in A-flat major, Op. 53 (french: Polonaise héroïque, ... {{Disambiguation, surname Language and nationality disambiguation pages ...
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Polish General Staff
Polish General Staff, formally known as the General Staff of the Polish Armed Forces (Polish: ''Sztab Generalny Wojska Polskiego'') is the highest professional body within the Polish Armed Forces. Organizationally, it is an integral part of the Ministry of National Defence and the Chief of the General Staff is the highest ranking military officer at the Ministry. It was created in 1918, and for a time bore the name Main Staff (''Sztab Główny''). Currently the position of Chief of the General Staff of the Polish Armed Forces (''Szef Sztabu Generalnego Wojska Polskiego'') is General Rajmund Andrzejczak, since 2 July 2018. History and structure On 25 October 1918, a decision was made to establish the directorate of the chief of staff of the Polish Army. In 1928 the General Headquarters of the Polish Army was established, known commonly at the time as the Main Staff (''Sztab Główny''). In September 1939, during the Invasion of Poland by the Wehrmacht and the Red Army, all the instit ...
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Leonard Danilewicz
Leonard Stanisław Danilewicz was a Polish 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. Cipher Bureau work AVA designed and built radio equipment for the Polish General Staff's Cipher Bureau, which was responsible for the radio communications of the General Staff's ''Oddział II'' (Section II, the General Staff's intelligence section). Beginning in 1933, after the Cipher Bureau's mathematician- cryptologist Marian Rejewski reconstructed the German military Enigma 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. AVA's other directors were Edward Fokczyński, Antoni Palluth, and Leonard Danilewicz's elder brother, Ludomir Danilewicz. The company took its name from the combined radio callsigns of the Danilewicz brothers (''TPAV'') ...
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Poles
Poles,, ; singular masculine: ''Polak'', singular feminine: ''Polka'' or Polish people, are a West Slavic nation and ethnic group, who share a common history, culture, the Polish language and are identified with the country of Poland in Central Europe. The preamble to the Constitution of the Republic of Poland defines the Polish nation as comprising all the citizens of Poland, regardless of heritage or ethnicity. The majority of Poles adhere to Roman Catholicism. The population of self-declared Poles in Poland is estimated at 37,394,000 out of an overall population of 38,512,000 (based on the 2011 census), of whom 36,522,000 declared Polish alone. A wide-ranging Polish diaspora (the '' Polonia'') exists throughout Europe, the Americas, and in Australasia. Today, the largest urban concentrations of Poles are within the Warsaw and Silesian metropolitan areas. Ethnic Poles are considered to be the descendants of the ancient West Slavic Lechites and other tribes that inhabit ...
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World War I
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was List of wars and anthropogenic disasters by death toll, one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fighting occurring throughout Europe, the Middle East, Africa, the Pacific Ocean, Pacific, and parts of Asia. An estimated 9 million soldiers were killed in combat, plus another 23 million wounded, while 5 million civilians died as a result of military action, hunger, and disease. Millions more died in Genocides in history (World War I through World War II), genocides within the Ottoman Empire and in the Spanish flu, 1918 influenza pandemic, which was exacerbated by the movement of combatants during the war. Prior to 1914, the European great powers were divided between the Triple Entente (comprising French Third Republic, France, Russia, and British Empire, Britain) and the Triple A ...
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EE Times
''EE Times'' (''Electronic Engineering Times'') is an electronics industry magazine published in the United States since 1972. EE Times is currently owned by AspenCore, a division of Arrow Electronics since August 2016. Since its acquisition by AspenCore, EE Times has seen major editorial and publishing technology investment and a renewed emphasis on investigative coverage. New features include The Dispatch, which profiles frontline engineers and unpacks the real-life design problems and their solutions in technical yet conversational reporting. Ownership and status ''EE Times'' was launched in 1972 by Gerard G. Leeds of CMP Publications Inc. In 1999, the Leeds family sold CMP to United Business Media for $900 million. After 2000, ''EE Times'' moved more into web publishing. The shift in advertising from print to online began to accelerate in 2007 and the periodical shed staff to adjust to the downturn in revenue. In July 2013, the digital edition migrated to UBM TechWe ...
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Telefunken
Telefunken was a German radio and television apparatus company, founded in Berlin in 1903, as a joint venture of Siemens & Halske and the ''Allgemeine Elektrizitäts-Gesellschaft'' (AEG) ('General electricity company'). The name "Telefunken" appears in: * the product brand name "Telefunken"; * ''Gesellschaft für drahtlose Telegraphie m.b.H., System Telefunken'', founded 1903 in Berlin as a subsidiary of AEG and Siemens & Halske; * ''Telefunken, Gesellschaft für drahtlose Telegraphie m.b.H.'' (from 1923 to 1955 – since 1941 subsidiary of the AEG only); * ''Telefunken GmbH'' in 1955; * ''Telefunken Aktiengesellschaft (AG)'' in 1963; * Merger of AEG and Telefunken to form ''Allgemeine Elektrizitäts-Gesellschaft AEG-Telefunken'' (from 1967 to 1979); * AEG-TELEFUNKEN AG (from 1979 to 1985); * ''TELEFUNKEN Fernseh und Rundfunk GmbH'', Hanover (1972, subsidiary of AEG-TELEFUNKEN); * Telefunken electronic GmbH (a spin-off of AEG-Telefunken and DASA * the company (since 1992) ...
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