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History
of Mobile Phones
The basic concept of cellular
phones began in 1947 when researchers looked at crude mobile
phones and realized that by using small cells with frequency
reuse could increase the traffic capacity of mobile phones
substantially, however, the technology to do it was nonexistent.
A mobile or cellular telephone
is a long-range, portable electronic device for personal telecommunications
over long distances.
Early years
Mobile rigs were the beginning of mobile phones, along with
taxicab radios, two way radios in police cruisers, and the
like. A large community of mobile radio users, known as the
mobileers, popularized the technology that would eventually
give way to the mobile phone.
Originally, mobile phones were permanently installed in vehicles,
but later versions such as the so-called "bag phones"
were equipped with a cigarette lighter plug so that they could
also be carried, and thus could be used as either mobile or
as portable phones.
First Generation Cellular
The first hand held mobile phone to become commercially available
was the Motorola DynaTAC 8000X, which received approval in
1983. Mobile phones began to proliferate through the 1980s
with the introduction of "cellular" phones based
on cellular networks with multiple base stations located relatively
close to each other, and protocols for the automated "handover"
between two cells when a phone moved from one cell to the
other.
At this time analog transmission was in use in all systems.
Mobile phones were somewhat larger than current ones, and
at first, all were designed for permanent installation in
cars .
In Switzerland, the name for the big car-based phone models
was "Nationales Autotelefon", and persists as the
common designation for mobile phones. Soon, some of these
bulky units were converted for use as "transportable"
phones the size of a briefcase. . Motorola introduced the
first truly portable, hand held phone. |
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Mobile-phone
culture and customs
In fewer than twenty years, mobile phones have gone from being
rare and expensive pieces of equipment used primarily by the
business elite, to a pervasive low-cost personal item. In
many countries, mobile phones now outnumber land-line telephones,
with most adults and many children now owning mobile phones.
In the United States, 70% of children own mobile phones. It
is not uncommon for young adults to simply own a mobile phone
instead of a land-line for their residence. In some developing
countries, where there is little existing fixed-line infrastructure,
the mobile phone has become widespread. According to the CIA
World Factbook the U.K. now has more mobile phones than people.
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Technology
Mobile phones and the network they operate under
vary significantly from provider to provider, and nation to
nation. However, all of them communicate through electromagnetic
microwaves with a cell site base station, the antennas of
which are usually mounted on a tower, pole, or building.
The phones have a low-power transceiver that transmits voice
and data to the nearest cell sites, usually 5 to 8 miles (approximately
8 to 13 kilometres) away. When the cellular phone or data
device is turned on, it registers with the mobile telephone
exchange, or switch, with its unique identifiers, and will
then be alerted by the mobile switch when there is an incoming
telephone call. The handset constantly listens for the strongest
signal being received from the surrounding base stations.
As the user moves around the network, the mobile device will
"handoff" to various cell sites during calls, or
while waiting between calls it will reselect cell sites.
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