Page "Mobile telephony" Paragraph 5

In 1947 Bell Labs was the first to propose a cellular radio telephone network.

The primary innovation was the development of a network of small overlapping cell sites supported by a call switching infrastructure that tracks users as they move through a network and passes their calls from one site to another without dropping the connection.

In 1956 the MTA system was launched in Sweden.

The first call on a handheld mobile phone was made on April 3, 1973 by Martin Cooper, then of Motorola to his opposite number in Bell Labs who were also racing to be first.

Bell Labs went on to install the first trial cellular network in Chicago in 1978.

This trial system was licensed by the FCC to ATT for commercial use in 1982 and, as part of the divestiture arrangements for the breakup of ATT, the AMPS technology was distributed to local telcos.

The first commercial system opened in Chicago in October 1983.

A system designed by Motorola also operated in the Washington D. C ./ Baltimore area from summer 1982 and became a full public service later the following year.

Japan's first commercial radiotelephony service was launched by NTT in 1978.