June 15, 2013

History of Cellular Telephony

History of Cellular Telephony

1947 Bell Laboratories introduced the idea of cellular communications with the police car technology.
1947 The basic concept of cellular phones began, when researchers looked at crude mobile (car) phones and realized that by using small cells (range of service area) with frequency reuse they could increase the traffic capacity of mobile phones substantially. However at that time, the technology to do so was nonexistent.
1947 AT&T  proposed that the FCC allocate a large number of radio-spectrum frequencies so that widespread mobile telephone service would become feasible.
1947 The FCC decided to limit the amount of frequencies available, the limits made only twenty-three phone conversations possible simultaneously in the same service area.
1968 AT&T and Bell Labs proposed a cellular system to the FCC of many small, low-powered, broadcast towers, each covering a 'cell' a few miles in radius and collectively covering a larger area. Each tower would use only a few of the total frequencies allocated to the system. As the phones traveled across the area, calls would be passed from tower to tower.
1968 The FCC reconsidered its position by stating "if the technology to build a better mobile service works, we will increase the frequencies allocation, freeing the airwaves for more mobile phones."
1973 (April) The first call on a portable cell phone is made by Dr Martin Cooper, a former general manager for the systems division at Motorola, who is also considered the inventor of the first modern portable handset.
1977 AT&T and Bell Labs had constructed a prototype cellular system. A year later, public trials of the new system were started in Chicago with over 2000 trial customers.
1979 The first commercial cellular telephone system began operation in Tokyo.
1980 Analog cellular telephone systems were experiencing rapid growth in Europe, particularly in Scandinavia, United Kingdom, France and Germany. Each country developed its own system, which was incompatible with everyone else's in equipment and operation
1981 Motorola and American Radio telephone started a second U.S. cellular radio-telephone system test in the Washington/Baltimore area.
1982 FCC authorizes commercial cellular service for the USA.
1982 The Conference of European Posts and Telegraphs (CEPT) formed a study group called the Groupe Sp├ęcial Mobile (GSM) to study and develop a pan-European public land mobile system.  The proposed system had to meet certain criteria:
  • Good subjective speech quality
  • Low terminal and service cost
  • Support for international roaming
  • Ability to support handheld terminals
  • Support for range of new services and facilities
  • Spectral efficiency
  • ISDN compatibility
1983 The first American commercial analog cellular service or AMPS (Advanced Mobile Phone Service) was made available in Chicago by Ameritech.
1987 Cellular telephone subscribers exceeded one million and the airways were crowded.
1989 GSM responsibility was transferred to the European Telecommunication Standards Institute (ETSI),
1990 Phase I of the GSM specifications were published.
1991 Commercial launch of cellular service based on GSM standard in Finland.

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