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Mobile
phone:
The mobile phone or mobile, also called a wireless,
cellular phone, cell phone (AKA: cellphone), cell or
hand phone (HP), 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,
and accessories, 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).
History
U.S. Patent 887,357
for a wireless telephone was issued in 1902
to Nathan B. Stubblefield
of Murray, Kentucky.
He applied this to "cave radio" telephones
and not directly to cellular telephony as the term is
currently understood. Cells for mobile phone base stations
were invented in 1947
by Bell Labs
engineers at AT&T
and further developed by Bell Labs during the 1960s.
Radiophones
have 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 and civil services in the 1950s, while hand-held
cellular radio devices have been available since 1973.
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 phones, 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 1983, Motorola
DynaTAC was the second approved mobile phone
by FCC. In 1984, 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, Motorola manager Martin Cooper made
the first call on a handheld mobile phone on April
3, 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
phone 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.[citation
needed][4] 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 portable 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 drive forward 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.
Manufacturers
Nokia
is currently the world's largest manufacturer of mobile
phones, with a global device market share of approximately
40% in Q4 of 2007. Other major mobile phone manufacturers
(in order of Market share) include Samsung
(14%), Motorola
(12%), Sony ericsson
(9%) and LG Mobile
(7%). These manufacturers account for over 80% of all
mobile phones sold and produce phones for sale in most
countries.
Other manufacturers include Apple
Inc., Audiovox
(now UTStarcom), Benefon,
BenQ-Siemens,
High Tech Computer Corporation
(HTC), Fujitsu, Kyocera, Mitsubishi Electric, NEC, Neonode,
Panasonic (Matsushita Electric), Pantech Curitel, Philips,
Research In Motion, Sagem, Sanyo, Sharp, Siemens, Sierra
Wireless, SK Teletech, Sonim Technologies, T&A Alcatel,
and Toshiba. There are also specialist communication
systems related to (but distinct from) mobile phones.
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