History
Main article: History of mobile phones
Various cell phones from the past 10-15 years:
The introduction of cells for mobile phone base stations,
invented in 1947 by Bell Labs engineers at AT&T, was further
developed by Bell Labs during the 1960s. Radiophones have a long and
varied history going back to the Second World War with military use
of radio telephony links and civil services in the 1950s, while
hand-held cellular radio devices have been available since 1983. Due
to their low establishment costs and rapid deployment, mobile phone
networks have since spread rapidly throughout the world,
outstripping the growth of fixed telephony.
In 1945, the zero generation (0G) of mobile telephones was
introduced. 0G mobile telephones, such as Mobile Telephone Service,
were not officially categorized as mobile phones, since they did not
support the automatic change of channel frequency during calls,
which allows the user to move from one cell (the base station
coverage area) to another cell, a feature called "handover".
In 1970, Bell Labs invented such a "call handoff"
feature, which allowed mobile-phone users to travel through several
cells during the same conversation. Motorola is widely considered to
be the inventor of the first practical mobile phone for handheld use
in a non-vehicle setting. Using a modern, if somewhat heavy portable
handset, they made the first call on a handheld mobile phone in
April, 1973.
The first commercial cellular network was launched in Japan by
NTT in 1979. Fully automatic cellular networks were first introduced
in the early to mid 1980s (the 1G generation) with the Nordic Mobile
Telephone (NMT) system in 1981. This was followed by a boom in
mobile telephone usage, particularly in Northern Europe.
The first "modern" network technology on digital 2G (second
generation) cellular technology was launched by Radiolinja (now part
of Elisa Group) in 1991 in Finland on the GSM standard which also
marked the introduction of competition in mobile telecoms when
Radiolinja challenged incumbent Telecom Finland (now part of
TeliaSonera) who ran a 1G NMT network. A decade later, the first
commercial launch of 3G (Third Generation) was again in Japan by NTT
DoCoMo on the WCDMA standard. However, Martin Cooper, a Motorola
engineer, is credited with the invention of the modern mobile phone
in the 1990s. Until the early 1990s, most mobile phones were too
large to be carried in a jacket pocket, so they were typically
installed in vehicles as car phones. With the miniaturization of
digital components, mobile phones have become increasingly handy
over the years.
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