News and Document archive source
copyrighted material disclaimer at bottom of page

NewsMine9-11flight93-ua — Viewing Item

Cell towers range 10 sq miles

Original Source Link: (May no longer be active)

(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:


(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.

Banned knife found in flight93 wreckage { March 22 2002 }
Cell phone tower sites 2 3 kilometers apart [pdf]
Cell phones dont work above 10k feet { April 8 2005 }
Cell phones dont work high altitudes
Cell phones typically dont work above 10 000 feet
Cell towers cover 10 sq miles [pdf]
Cell towers outside range of airline cruising altitude
Cell towers range 10 sq miles
Cheney ordered shot down { January 25 2003 }
Company tests new system cell phones in flight
Debris appears miles from crash site { September 13 2001 }
Fbi refused flight93 tape
Federal officials reinforce story of 911 passenger heros { June 5 2004 }
Flight 93 headed towards johnstown airport { September 13 2001 }
Flight 93 heros inspire neil young song { December 16 2001 }
Flight 93 norad tapes released
Flight 93 requests clearance to washington { September 11 2001 }
Flight 93 was shot down claims book
Flight93 debris 8miles
Flight93 mystery { November 15 2001 }
Flight93 shot down { September 14 2001 }
How cell phones work [pdf]
Imporable truth
Most passengers from flight 93 used cell phones
New fbi view flight93
New study sells dont try cell phones on plane { March 3 2006 }
New systems allow cell phones during flight { June 15 2005 }
Passengers expect to use cell phones after 911 { June 9 2005 }
Pentagon video release to rest conspiracy theories { May 16 2006 }
Prepared to order aircraft shoot down
Report says hijackers ordered crash
Riddle hijacked get crash site
Rumsfeld says flight 93 shot down { December 27 2004 }
Seismologist discrepancy
Shoot down flight 93
Somebody asked faa for new flight plan
Victim husband says pentagon video shows nothing { May 17 2006 }

Files Listed: 37


CIA FOIA Archive

National Security
Support one-state solution for Israel and Palestine Tea Party bumper stickers JFK for Dummies, The Assassination made simple