The mobile phone, cellular phone, or simply cell phone
is a long-range, portable electronic device used for mobile communication that uses a
network of specialized base stations known as cell sites. In addition to the standard voice
function of a telephone, current mobile phones can support many additional services such as
SMS for text messaging, email, packet switching for access to the Internet, and
MMS for sending and receiving photos and video. Most current mobile phones connect
to a cellular network of base stations (cell sites), which is in turn interconnected to the
public switched telephone network (PSTN) (the exception is satellite phones).
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. 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.
Today, video and TV services are driving forward third generation (3G) deployment.
And in the future, low cost, high speed data will driveforward the fourth generation
(4G) as short-range communication emerges. Service and application ubiquity, with
a high degree of personalization and synchronization between various user appliances,will
be another driver. At the same time, it is probable that the radio access network
will evolve from a centralized architecture to a distributed one.
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