Mobile phone
“Cell Phone” redirects here. For the 2003 Chinese film,
see Cell Phone (film).
Several mobile phonesA mobile or cellular telephone (commonly, "mobile
phone" or "cell phone") is a long-range, portable
electronic device used for mobile communication. 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 are satellite phones).
Mobile phones are distinct from cordless telephones, which generally
operate only within a limited range of a specific base station.
Technically, the term mobile phone includes such devices as satellite
phones and pre-cellular mobile phones such as those operating via
MTS which do not have a cellular network, whereas the related term
cell(ular) phone does not.
HISTORY
Today's widespread use of mobile phones was made possible by the
introduction of hexagonal cells for mobile phone base stations,
invented in 1947 by Bell Labs engineers at AT&T and 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 0G generation of mobile telephones were 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 in the middle of a call,
when the user moved from one cell (base station coverage area) to
another cell, a feature called "handover".
In 1970 Amos Joel of Bell Labs invented the "call handoff"
feature, which allowed a mobile-phone user to travel through several
cells during the same conversation. Martin Cooper of 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, Cooper made the first call on
a handheld mobile phone on April 3, 1973. At the time he made his
call, Cooper was working as Motorola's General Manager of its Communications
Division.
Fully automatic cellular networks were first introduced in the
early to mid-1980s (the 1G generation). The first fully automatic
mobile phone system was the 1981 Nordic Mobile Telephone (NMT) system.
Until the late 1980s, most mobile phones were too large to be carried
in a jacket pocket, so they were usually permanently installed in
vehicles as car phones. With the advance of miniaturization and
smaller digital components, mobile phones got smaller and lighter.
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