History of wireless communication

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HISTORY OF WIRELESS COMMUNICATION

History of wireless communication

  1. 1. HISTORY OF WIRELESS COMMUNICATION AJAL.A.J Assistant Professor –Dept of ECE, Federal Institute of Science And Technology (FISAT) TM   MAIL: ec2reach@gmail.com
  2. 2. @ 150 BC• The use of smoke signals for communication ( mentionedd by polybius – Greece)
  3. 3. @ 206 BC – 24 AD• Han Dynasty in Ancient China . ( light was used for signalling messages along a  line of signal towers towards the capitol  Chang’an –  { Xi’an}   )
  4. 4. Note • Using light and flags for wireless communication remained important for the navy until radio transmission was introduced.ImportanceEven today a sailor has to know some codes represented by flags if all other means of wireless communication fail
  5. 5. @ 1974Claude chappe• It was not until the end of the 18 th centuary, when Claude chappe invented – Optical Telegraph• that long- distance wireless communication was possible with technical means.• Optical Telegraph lines were built almost until the end of the following centuary.
  6. 6. @1843 • Wired communication started with the first commercial telegraph line between Washington Baltimore•Alexander Graham Bells invention & marketing of telephone in  1876 •Others tried before but didn’t succeed Example – Philips Reis ,  (1834- 1874) – who discovered the telephone principle
  7. 7. @1881• In Berlin, a public telephone service was available in 1881
  8. 8. @ 1936• The first regular public voice & multimedia video service Was available in 1936  between Leipzig Berlin
  9. 9. Note• At that time , it was not possible to focus light as efficiently as can be done today by means of a laser, wireless communication did not really take off until the discovery of EM waves &The development of the equipment to modulate them
  10. 10. @ 1831• It all started with michael Faraday ( and about the same time Joseph Henry )• Demonstrating EM induction in 1831 &• James C Maxwell ( 1831- 1879) laying the theoretical foundation for EM fields with his famous equations @ 1864
  11. 11. @ 1857- 1894• Heinrich Hertz was the first to demonstrate the wave character of electrical transmission through space (1886) thus providing Maxwells equations.NoteToday the unit Hz reminds us of this discovery.
  12. 12. @ 1856 - 1943• Nikola Tesla (1856 - 1943 ) soon increased the distance of EM transmission
  13. 13. @ 1874 - 1937• The name , which is most closely connected with the success of wireless communication , is certainly that of Guglielmo Marconi (1874 – 1937)• He gave the 1 st demonstration of wireless telegraphy in 1895 using long wave transmission with , very high transmission power ( > 200 K w )
  14. 14. @ 1901• The first transatlantic transmission followed in 1901
  15. 15. @ 1906• WARC – World Administration Radio Conference took place , cordinating world wide use of radio frequencies• The 1 st radio broadcast tookplace in 1906 when Reginald A Fessenden  transmitted voice and music for christmas
  16. 16. @ 1906   contd …..• The invention of electronic vaccum tube in 1906 byLee De Forest ( 1873- 1961) &Robert Von Lieben ( 1878 – 1913 )Helped to reduce the size of sender and receiver
  17. 17. @1907• Only 6 years later in 1907 , 1 st commercial transatlantic connections were setup .• Huge Base Stations using upto thirty 100 m high antennas where needed on both sides of the atlantic ocean
  18. 18. @ 1911• One of the 1 st mobile transmitter was on board at Zeppelin in 1911
  19. 19. @ 1915• In 1915 , the first wireless voice transmission was set up between New York San Francisco
  20. 20. @ 1920• The 1 st commercial radio station started in 1920 [ KDKA – from pittsburgh ]NoteSender & Receiver still needed huge antennas&High transmission power.
  21. 21.  @ 1920      contd…• This changed fundamentally with the discovery of – short waves again by Marconi in 1920( in connection with wireless communication , short waves have the advantage of being reflected at the ionosphere)
  22. 22. @ 1926• As early as 1926, the first telephone in a train was available on the Berlin – Hamburg line Note Wireless parallel to the railroad track worked as antenna
  23. 23. @ 1927• The first car radio was commercially available in 1927 ( philco Transitone )• NOTE George Frost an 18 year old from Chicago had integrated a radio into a Ford Mode T as early as 1922
  24. 24. @ 1928• 1928 was the year of many field trials for TV broadcasting.• John L Baird ( 1888 – 1946 ) transmitted TV across Atlantic and demonstrated colour TV
  25. 25. @ 1932• The first tele teaching started in 1932 from the CBS station .• Uptil then , all wireless communication used AM which offered relatively poor quality due to interference
  26. 26. @ 1933• One big step forward in this respect was the invention of FM in 1933 by• Edwin H Armstrong [ 1890 - 1954 ] both the fundamental modulation schemes are still used for todays radio broadcasting with FM having much better quality
  27. 27. @ 1958• After II nd world war , the first network in Germany was the analog A- Netz from 1958, using a carrier frequency of 160 Mhz.• Connection setup was only possible from the mobile station and no handover ie: changing the base station was possible
  28. 28. @ 1982• In acordance with the general idea of European Union , European countries decided to develop a pan – European mobile phone standard in 1982 ant their aim was :-1. Use a new spectrum at 900 MHz2. Allow roaming throughout Europe3. Be fully digital4. Offer voice & data service It was GSM
  29. 29. @ 1986• The northern European countries of Denmark Finland Cradle of modern mobile communication Norway SwedenAgreed upon the NMT { Nordic Mobile Telephone } system .•The analog NMT uses 450 Mhz carrier
  30. 30. GSMGroupe Speciale Mobile
  31. 31. @  1983• In 1983 the US system AMPS [ Advanced Mobile Phone System ] Started .• AMPS is analog & working at 850Mhz
  32. 32. @1990• The early 1990s marked the beginning of fully digital systems.• In 1991, ETSI adopted the standard –DECT [ Digital European Cordless Telephone ]• DECT works at a spectrum of (1880-1900) Mhz.
  33. 33. Roaming• Roaming means a seamless handover oa a telephone call From  one N/W provider To  anotherWhile crossing national boundaries

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