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Communication-System-at-a-Glance

By Ashik

 
Historical review
ā€¢Early history of communication

ā€¢1799 Alessandro Volta invented electric battery,
ā€¢1837 Samuel Morse demonstrated telegraph and 1844 first telegraph line (Washington-Baltimore) became operational
ā€¢Early history of wireless communication
ā€¢1831 Faraday demonstrates electromagnetic induction
ā€¢J. Maxwell (1831-79): theory of electromagnetic Fields, wave equations (1864)
ā€¢H. Hertz (1857-94): demonstrates with an experiment the wave character of electrical transmission through space(1888, in Karlsruhe,Germany, at the location of todayā€™s University of Karlsruhe)
 


 
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Historical review
  •    Early history of wireless communication I
  •     1895 Guglielmo Marcon
  •     first demonstration of wireless telegraphy (digital!)
  •     long wave transmission, high  transmission power necessary (> 200kw)





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