The history of mobile phones charts the development of devices which connect wirelessly to the public switched telephone network. The transmission of speech by radio has a long and varied history going back to Reginald Fessenden's invention and shore-to-ship demonstration of radio telephony, through the Second World War with military use of radio telephony links. Hand-held radio transceivershave been available since the 1940s. Mobile telephones for automobiles became available from some telephone companies in the 1940s. Early devices were bulky and consumed high power and the network supported only a few simultaneous conversations. Moderncellular networks allow automatic and pervasive use of mobile phones for voice and data communications.
In the United States,
engineers from Bell Labs began work on a system to allow mobile users to place
and receive telephone calls from automobiles, leading to the inauguration of
mobile service on June 17, 1946 in St. Louis, Missouri. Shortly after, AT&T offered Mobile Telephone Service. A wide
range of mostly incompatible mobile telephone services offered limited coverage
area and only a few available channels in urban areas. The introduction of
cellular technology, which allowed re-use of frequencies many times in small
adjacent areas covered by relatively low powered transmitters, made widespread
adoption of mobile telephones economically feasible.
The advances in
mobile telephony can be traced in successive generations from the early "0G" services
like MTS and its successor Improved Mobile Telephone Service, to first
generation (1G) analog cellular network, second generation (2G) digital
cellular networks, third generation (3G) broadband data services to the current
state of the art, fourth generation (4G) native-IP networks.
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