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Cell towers range 10 sq miles Original Source Link: (May no longer be active)
http://electronics.howstuffworks.com/cell-phone.htmhttp://electronics.howstuffworks.com/cell-phone.htm
(information retrieved Nov 24, 2006)
In a typical analog cell-phone system in the United States, the cell-phone carrier receives about 800 frequencies to use across the city. The carrier chops up the city into cells. Each cell is typically sized at about 10 square miles (26 square kilometers). Cells are normally thought of as hexagons on a big hexagonal grid, like this:
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http://www.mobiledia.com/guides/page1.html
(information retrieved Nov 24, 2006)
Explaining Cell Phone Reception
How Cell Phones Work
Cell phones are essentially "radios." They communicate to the world by transmitting and receiving voice through cell towers setup throughout the area. And a carrier's coverage is a network of cell sites, each with a tower and base station controller for a range of about 10 square miles.
From a carrier's standpoint, great coverage comes at various technological expenses and certain restrictions that are out of their control. For instance, each provider is limited by the FCC to a number of frequencies it can use in any given city.
Given a limited number of frequencies available in the spectrum, in order to sustain the capacity needed for urban coverage, frequency reuse is required.
To put it into an extreme example, if there was only one tower covering all of New York City, only a limited amount of simultaneous users could use that tower at once due to FCC regulations, say 100 frequency slots. Thus, 100 users at once could use it.
Conversely, if each house had its own tower, 100 users would be able to talk on their cell phones simultaneously in each house. Since each tower now only has a few feet to cover, power consumption is greatly lowered. Once a guest walks to a neighbor's apartment, the current tower would hand off the user to the next tower, freeing up a spot of another person.
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