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Digital Cell Phone

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GSM establishes an internationally accepted standard cellular network.     The compact Sony CM-H444 mobile seen here in its charging stand, was introduced in 1994. * By the early 1980's, analog telephone systems were attracting ever more customers. * Each country, however, was developing its own standard,which was often incompatible with others. * Standardization seemed essential, and so, in 1982, the Groupe Special Mobile (GSM) was established     by  a consortium of thirteen telecommunication interests to develop a common cell phone system   throughout Europe. * Appropriately, the acronym was later changed to represent the words "Global Systems for   Communications." * The first GSM phone call was made on the Finnish Radiolinja network in 1991, and by 1997 100   countries had implemented a GSM capable network. * GSM strove to produce a standard for all the elements of cellular mobile phone call, including the   particular frequencies to be used for receiving and transmi