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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. 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. | |
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