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Mobile phones are looked upon as a modern invention. However, their origin can be traced back to the invention of telephone way back by Graham Bell in 1870s and success in the capture of radio message. Since those events, these basis technologies have merged and shaped themselves together as mobile phone.
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Summing up the history of mobiles phones we can say that the Telephones were the beginning of the whole system. Radio charted the progress of radio communications. Both technologies came together to bring Radio Telephones. Then came Cellular which marked the development of the popular cellular mobile phone systems. Another step was Digital which led to the emergence of a digital standard, GSM. Satellites helped mobile phones emerge as the preferred medium of communication at the global level.
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Alexander Graham Bell patented the telephone in 1876. The device was initially developed using the technology designed for the telegraph and started out as a manually-switched network. Calls were connected by operators. Another pillar of mobile telephony came into being when Charles Stevenson developed radio communication in the early 1890s to keep in contact with off-shore lighthouses. Marconi transmitted a signal over a distance of 2 km in 1894. Fessenden was able to broadcast music by radio in 1906.
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In early 1920s in the United States, mobile radios began operating at 2 MHz. These mobile radios were used only by the police on experimental basis. However, practical systems were not implemented until the 1940s. Development of the system was done keeping the police and emergency services requirements in mind. Public use of mobile technology was not yet thought.
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Commercial Mobile Telephony goes back to the 1940s, when digital wireless and cellular roots came into being. The transistor, invented in 1948, made it possible to build smaller, cheaper and lighter devices. While early telephone network worked on the vacuum tube and the transistor, the wireless revolution began only after low cost microprocessors and digital switching became available.
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New mobile phone system called Total Access Control System (TACS) made possible efficient use of frequencies. The system had the mobile phones connected to smaller, lower-powered base stations arranged in a cellular pattern. Hence the name cellular phone. However, limitation of Analogue technology led to the development of Global System for Mobile Communications technology.
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