Cell Phone History
In the early 1920s the Detroit Police Department was the first government agency to use mobile radiotelephones in their patrol cars. At this time only one-way service was available, the pertinent information could be sent to the police vehicle but no response to the call was possible. Some five years later two-way service was introduced by a police department in New Jersey. This capability was then also made available for those private citizens that could afford it. The basic concept of cellular phones began in 1947, when researchers looked at crude mobile (car) phones and realized that by using small cells (range of service area) with frequency reuse they could increase the traffic capacity of mobile phones extensively. Unfortunately at the time, the technology did not exist. In 1947, AT&T proposed that the FCC (F
Public cell phone testing began in 1977. ederal Communications Commission) designate a large number of radio-spectrum frequencies so that widespread mobile telephone service would become feasible and AT&T would have an incentive to research the new technology. " By 1987, however, it was clear that something needed to be done about eventual overcrowding of cell phone frequencies, there were already more then a million cell phone subscribers. " Both AT&T and Bell Labs proposed a cellular system to towers, each covering a "cell" a few miles in radius and collectively covering a larger area. The Telecommunications Industry Association set a new standard with the creation of the TDMA Interim Standard 54, in 1991. This in turn, was not a market incentive for research. These imposed limits, only allowed twenty-three simultaneous phone conversations possible in the same service area. The FCC again came up with a solution: allow companies to research different technologies that could somehow free the cell phone airways. In 1983, "the first American commercial analog cellular service was made available in Chicago by Ameritech. Many place blame on the FCC for the gap between the initial concept of cellular service and its availability to the public. A couple of years later, the FCC authorized commercial cell phone use in the United States. The idea was that as the phones traveled across the area, calls would be passed from tower to tower. Companies then began developing new alternatives to the current system.
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