1 history of telecom & evolution


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1 history of telecom & evolution

  1. 1. EEE354 Telecommunication Systems Engineering By Irfan Latif Khan Irfan khan
  3. 3. DEFINITION OF TELECOMMUNICATIONS Telecommunications eliminated a master-to-servant relationship: replacing the service of a messenger by mechanical telegraph in 1794, by copper wires in 1837, by electromagnetic waves in 1896, and by optical fiber in 1973. The word telecommunication, adding tele (= distance), was created by Edouard Estaunie´ (1862–1942) in 1904 in his book Traite´ pratique de te´le´communication electrique (te´le´graphie–te´le´phonie) In his book he defined telecommunication as ‘‘information exchange by means of electrical signals.’’ Estaunie´ thus limited telecommunications explicitly to ‘‘electrical signals.’’ Irfan khan
  4. 4. Irfan khan
  5. 5. DEFINITION OF TELECOMMUNICATIONSBy International Telecommunication Union (ITU) The International Telecommunication Union (ITU) originally recognized the term telecommunications in 1932 and defined it as: ‘‘any telegraph or telephone communication of signs, signals, writings, images and sound of any nature, by wire, radio, or other system or processes of electric or visual (semaphore) signaling.’’ Currently, the ITU defines telecommunications as ‘‘any transmission, emission, or reception of signs, signals, writings, images, and sounds; or intelligence of any nature by wire, radio, visual, or other electromagnetic systems.’’ Irfan khan
  6. 6. The trunk of the treerepresents the technologicalprerequisites for successiveunfolding of the varioustelecommunication domainsinto the branches of the treeThe leaves of the branchesrepresent evolution within the Telecommunicationsseparate telecommunication treedomains Irfan khan
  7. 7. EVOLUTION OF TELECOMMUNICATION The bases of telecommunications, and thus the roots of the tree, are science and industrialization. Optical telegraphy became possible, and thus telecommunications could grow, once the telescope was available and basic mechanical constructions could be made with sufficient accuracy The theory of electromagnetism and the development of precision mechanics nourished the growth of an electrical telegraphy branch. Electrical telegraphy started with code-writing telegraphs and needle telegraphs and so on.Copper-line transmission systems: Basic laws of electricity and the discovery of gutta-percha began the evolution of copper-line transmission systems on open wire, copper cable, and coaxial cable. Irfan khan
  8. 8. EVOLUTION OF TELECOMMUNICATION The basic theory of sound developed by Helmholtz supported the evolution from telegraphy to telephony. The early automation of industrial processes enabled the replacement of manual switchboards by automatic switching devices. The discovery of electromagnetic radiation and the subsequent development of devices for generating and detecting such waves led to the development of radio-telegraphy. The creation of electronic tubes (diodes and triodes) started the electronic era, which enabled the evolution from radio-telegraphy to radio-telephony and mobile radio. Irfan khan
  9. 9. EVOLUTION OF TELECOMMUNICATION The feedback principle applied in electronic circuitry facilitated the generation of high frequencies and thus the development of medium- and shortwave radio transmission and a new technology of circuit combination: carrier frequency, or multiplexing. The development of very high frequency generators in 1920 and velocity-modulated electronic tubes in the early 1930s made radio- relay transmission possible, Rockets, transistors, and solar cells were the ingredients for the satellite branch. The laser and extremely pure glass enabled the fiber optics branch to grow. ICs (integrated circuits) and microprocessors were the nourishment for the cellular radio branch. The convergence of communications and computers (C&C) and the application of CD-ROMs for high-volume data storage is currently leading to multimedia services Irfan khan
  10. 10. EVOLUTION OF TELECOMMUNICATION(FUTURE) The first new leaf will probably represent an entirely new range of combined optical transmission- switching systems. Another leaf might represent wireless broadband links in metropolitan areas provided by ‘‘subspace’’ flying base stations located in unmanned balloons and airplanes circling in the stratosphere. Irfan khan
  11. 11. Within two centuries telecommunications experiencedtremendous progress.This development is best demonstrated by the example oftransatlantic submarine cable transmission:1866. The first transatlantic telegraph cable installed.Morse-coded telegraph channel with a speed of about 5 words perminute. 1956. The first transatlantic telephone cable installed. operated 36 telephone channels on two separate cables. 2000. The state-of-the art transatlantic fiber optic cable installed. 12 fibers each with a capacity of 40 WDM 10-Gbps channels, thus a total of 4.8 Tbps, which is equivalent to 58,060,800 telephone channels. Irfan khan
  12. 12. Chronology of telecommunications. Irfan khan
  13. 13. Classical telecommunication networks. Irfan khan
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  15. 15. MAJOR CREATORS OF TELECOMMUNICATIONS These persons, in their time, usually faced strong opposition and needed to put forth substantial effort to obtain recognition and acceptance of their invention. Claude Chappe (1763–1805) Claude Chappe began the era of telecommunications with the successful operation of his optical telegraph between Paris and Lille on August 15, 1794 he committed suicide at the age of 42 as depressed by the people. Samuel Finley Breese Morse (1791–1872) The electrical telegraph had many ‘‘fathers’’ and they all developed unique solutions. But, the writing telegraph of Morse proved its superiority and found worldwide use. Irfan khan
  16. 16. Alexander Graham Bell (1847–1922) The telephone era begun in 1876 in the United States with the operation of a telephone line across a 2-mile stretch between Boston and Cambridge, Massachusetts, with telephone apparatus produced by Bell.Heinrich Rudolf Hertz (1857–1894) Heinrich Hertz laid the basis for radio transmission with successful experiments in 1887–1889 that proved the existence of electromagnetic radiation and its similarity to the behavior of light. Unfortunately, he became ill and died at the age of 37.Guglielmo Marconi (1874–1937) Marconi succeeded in transmitting a radio signal over a few kilometers at Bologna in 1896.Alec H. Reeves (1902–1971) Alec H. Reeves conceived the idea of digitizing speech and patented his pulse-code-modulation (PCM) procedure, but at a time when the prevailing technology prevented its economical realization. Irfan khan
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  18. 18. OPTICAL TELEGRAPHY Tachygraphe of Claude Chappe. Irfan khan
  19. 19. OPTICAL TELEGRAPHY Optical telegraph of Chappe, paris terminal. Irfan khan
  20. 20. OPTICAL TELEGRAPHY French optical telegraph network around 1850. Irfan khan
  21. 21. OPTICAL TELEGRAPHY 1917 The last optical telegraph line closes on Curacao (island in the southern Caribbean Sea, off the Venezuelan coast ). Restored optical telegraph station at Chatley Heath. Irfan khan
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  23. 23. Electrical Telecommunication The most important invention paving the way toward electrical telecommunications was made in 1799. When Alessandro Volta (1745– 1827), constructed an electrolytic cell, later called a voltaic pile or voltaic cell. This was the first continuous source of electricity became available Irfan khan
  24. 24. Electrical TelecommunicationSeries of discoveries that turned attention towardelectromechanical signaling. With in three decades resulted in electrical telegraphy. 1820 Hans Christian Oerstedt discovers the electromagnetic field. Ampe`re discovers electrodynamics. Johann S. Ch. Schweigger develops the galvanometer. 1825 William Sturgeon constructs the first electromagnet. 1826 Georg Simon Ohm defines the basic electrical law V = IR. 1830 William Ritchie demonstrates electrical telegraphy. 1831 Michael Faraday discovers electromagnetic induction. Irfan khan
  25. 25. ELECTRICAL TELEGRAPHY Almost simultaneously, in 1837, Cooke together with Wheatstone presented an electrical needle telegraph in Great Britain . And Morse an electrical writing telegraph in the United States.Electrical needle telegraphCode presentation for the one-needle Three versions of needle telegraphs fromtelegraph of Cooke and Wheatstone. Cooke and Wheatstone. Irfan khan
  26. 26. ELECTRICAL TELEGRAPHYElectrical pointer telegraph ABC pointer telegraph. Siemens’s pointer telegraph. Irfan khan
  27. 27. ELECTRICAL TELEGRAPHYElectrical writing telegraph Lever-transmitter making and breaking the electrical circuit when it moved up and down, soon generally known as the Morse key. With this key the telegraph receiver produced discrete dots and dashes of deferent lengths. Morse telegraph as used for the Replica of Morse’s first Washington–Baltimore line. electrical writing telegraph Irfan khan
  28. 28. TELEGRAPH TRANSMISSION TECHNOLOGYOptical telegraphy Air was the transmission mediumElectrical telegraphy 1.Open-Wire Lines -One station to another via overhead copper lines -Low electrical resistance, costly, limited mechanical strength -Frequently stolen or damaged by storm and ice loads. -Copper was very soon replaced by galvanized iron, to reduce theft and to increase mechanical strength. -Hard-drawn copper wire with good mechanical strength was invented in the United States. -The electromagnetic relay became a general purpose device to repeat, regenerate, or amplify telegraph signals in route over increasingly long lines. The relay is thus the first piece of line transmission equipment Irfan khan
  29. 29. 2.Underground Cable Open-wire lines are very vulnerable to damage by natural calamities and cannot be used for large water crossings. For underground cables insulation and protection was issue. Initially lead-sheathed cable was used for river crossing. Discovery of Gutta-percha proved to be an excellent insulation material for underwater cables.3. Submarine Cable The assumption that an ocean had a smooth and calm floor proved to be wrong; strong surface currents and stony peaks broke the first cables. Cable at a depth of 6000 to 8000 m has to withstand tremendous pressures. Strong mechanical armoring was applied, brass tape was wound around the copper conductor as additional protection Laid not in a straight line but with substantial slack Irfan khan
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  31. 31. Telegraph Era in Indo Pak1839 The British physician Sir William Brooke installed an experimental electrical telegraph line near Calcutta .1850 An electrical telegraph line was established in Calcutta between Diamond Harbor and the center of Calcutta.1855 Within four years a star-shaped network with a total length of 7000 km connected the capital Delhi with Peshawar in the far north, Calcutta in the east, Madras in the south, and Bombay in the west1858 The first submarine cable was laid in India between the mainland and the island of Ceylon Another remarkable telegraph line was installed down the Himalayan1895 Mountains in 1895, connecting the town of Gilgit with the Indian telegraph network. Iron masts about 10 m high supported the strong steel wires over snow heights up to 6 m. Irfan khan
  32. 32. Indian telegraph network in 1855. Irfan khan
  33. 33. Telecommunicationhistory in Pakistan (PTCL) Major Events1947 1962 1990-91 1995 1996 1998 1999 Converted into Draft Telecom Pakistan About 5 % Policy Posts & Telecom Corp* of PTC Mobile serviceTelegraph ALIS: 850,000 assets licence PTMLDept. Waiting list : transferredestablished 900,000 Expansion to PTA,FAB Mobile, Internet and Payphone Program of 900,000 & NTC subsidiary companies established lines initiated Renamed as (500,000 lines by PTC converted into Pakistan Private Sector PTCL** Telegraph and Participation -Public Limited *PTC Act No.XVIII of 1991 Telephone 400,000 lines Company listed at **Pak Telecomm Re org Deptt. PTC/GOP KR,LH,IBD Stock Act No.XVII of 1996 own resources) Exchanges Irfan khan
  34. 34. History• 1994: Policy & Legal Framework.• 1996: Telecoms Reorganization Act• 1994/97: Pakistan’s acceptance to WTO Telecom Accord• 1996: NTC, PTA & FAB established• 1996: PTCL given 25 years License with 7 years exclusivity in Basic Telephony all over Pakistan except Northern Areas & AJK.• 1998: PTML, a subsidiary of PTCL, gets GSM 900 license.• 1996-99: Internet/Data/Payphone & V.A.services licensed liberally.• 1999: NTC licensed to provide telecom services to GoP/ Defence.• 2000: SCO licensed to provide telecom service in Northern Areas & Azad Jammu & Kashmir• 1999-2000: Liberalization initiatives taken on » Satellite segment/GMPCS licensing » Submarine FO cable landing rights Irfan khan
  35. 35. Basic Facts &Network Overview (Domestic) (As on May, 2001) • Installed Lines (ALI) 4.029 M Digital 3.592 M Analouge 0.389 M Manual 0.048 M • Working Lines (ALIS) 3.238 M Digital 2.999 M (0.05 M-rural) Analouge 0.211 M Manual 0.027M • Local Telephone Exchanges 2,685 Digital 1807 Analog 254 Manual 624 Digital Transit Exchanges 36 Irfan khan
  36. 36. Overview (Domestic) (As on May, 2001)• Digitalization 92%• Country Tele-density 2.45%• NWD Stations 1490• Optic Fibre Cable Network 5,570 KmPublic Call Offices• Urban 3,100• Rural 12,868• Pay Card Phones (urban) 48,926 Total 54,884 Irfan khan
  38. 38. PTCL Revenues Installation Installation Intl I/C 1% Intl I/C 1% 41% 44% Line Rent Rs.18,945 MRs.17,707 M 4% Line Rent Others 9% 0% Others 0% Intl O/G Local Calls 10% 18% Domestic Calls Intl O/G Domestic Calls 19% 9% Local Calls 24% 20% 1996-97 Rs. 40,594 M 1997-98 Rs. 46,466 M Intl I/C Installation 40% 3% Rs.20,573 M Others Line Rent 2% 9% Intl O/G 9% Local Calls Domestic Calls 20% 17% 1998-99 Rs.51,187M Irfan khan
  39. 39. Revenues 1999-00 Intl I/CRs.20,284M 35% Installation 2% Others 3% Intl O/G Line Rent 8% 13% Domestic Calls Local Calls 17% 22% Rs.58,643 M Irfan khan
  40. 40. Class discussion about current and futuresituation of telecommunication in Pakistan with respect to system engineering. Thank You Irfan khan