History of Mobile phones
I chose these theme because the cellphones, right now are an essential part of our lives.
Everyone has a cellphone, there are cellphones that are really cheap and are others that are expensive, but they have a lot of accessories, like television, internet, cameras and lot of stuff. These technology is getting bigger and in a future I think the cellphones will beinserted in our skin like microchips.
In the beginning, two-way radios were used in vehicles like taxicabs, police cruisers and ambulances, but they weren`t considered cellphones, because they weren`t connected to the telephone network. Users couldn`t dial a phone number from their vehicles, these radios only work to talk with another person that had a radio, the police officers used it to talk tothe office and to report incidents in the streets.
The later versions of this two-way radios, were called “so-called transportable or bag phones”, that were equipped with a cigarette lighter plug, so they also could be carried and this could be used as either mobile or as portable two-way radios.
In 1910 Lars Magnus Ericsson installed telephone in his car, but this wasn`t a radio telephone,because while he was traveling across the country he needed to stop at a place where he could use telephone lines and with two long electric wires he connect to the telephone network.
In Europe, the first radio was used on the first-class train passenger between Berlin and Hamburg in 1926. At the same time, radio was introduced on passenger airplanes for air traffic security.
Later it wasdeveloped in the German tanks during the second world war. When the war finished, the German police used those radios and this was the beginning of the first patrol cars, those service was used by people that were trained to use them, but in the 1950`s they could be used by untrained officers.
During the early 1940`s, Motorola developed a backpacked two-way radio for the US military, this radio workedwith batteries and was about the size of a man`s forearm.
In 1946 the soviet engineers G. Shapiro and I. Zaharchenko tested their version of a radio mobile phone mounted inside a car, and it could be connected to the local telephone network with a range of up to 20 kilometers.
Pioneers of Cellphone
Here are the most important dates of the invent of cellphone:
• In December 1947,Douglas H. ring and W, Rae Young, Bell lab engineers, proposed the hexagonal cells for mobile phones in vehicles. Phillip T. Porter, proposed that the cell towers be at the corners of the hexagons rather than the centers and have directional antennas that would transmit and receive in 3 directions into 3 adjacent hexagon cells.
• The recognizable mobile phones with direct dialing have existedsince 1950`s, an example of this is that in the movie Sabrina in 1954, a man makes a call from the phone in the back of a limousine.
• The first fully automatic mobile phone system called MTA, was developed by ericsson and commercially released in Sweden in 1956.
• In 1957 the soviet radio engineer Leonid Kupriyanovich from Moscow created the portable mobile phone named LK-1. Thismobile phone was consisted of a relatively small handset equipped with an antenna, rotary dial and communicated with a base station.
• The LK-1 had 3 Kg weigh and it could operate up to 30 kilometers, with a 20 hours of battery life.
• In 1958, Kupriyanovich resized his LK-1 to pocket version, with a weight of 500grams. In the same year the USSR began to deploy the Altay that was anational civil mobile phone specially for motorists. The main developers of the Altay system were the Voronezh science research institute of communications(VNIIS) and the State Specialized Project Institute(GSPI).
• But the technology didn`t exist then, and the cellular technology was undeveloped until the 1960`s.
• In 1963 the Altay service started in Moscow and in 1970 the Altay...
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