Cell phones history dates back to the 1940?s. The digital wireless and cellular phones have progressed at a fast rate in the last 60 years (Telecom, 2000). More than 110 million people have use of cellular phones today (Backover, 2001). The time Americans spend on the their cell phones has risen over the past years. It has gone from 89 billion minutes in 1998 to nearly 200 billion in just the first six months of 2001 (Consumer, 2002). Cell phones are great gadgets in which you can speak to anyone in the world from anywhere. The functions of cell phones are being updated at continuously (Brain, 1998-2002).
?Depending on the cell phone model, you can: Store contact information Make tasks or to-do list Keep track of appointment Use of built in calculators for simple Math Send or receive Email Get information from the Internet Play games Download songs (Brain, 1998-2002).?
English: Mobile phone evolution Русский: Э...
A Japanese cell phone with various stickers and ch...
English: Cell phone tower near the village of Loze...A cell phone is actually a sophisticated form of a radio. The cellular system divides a city into small cells. This allows extensive frequency reuse across the city so that many people can use their cell phones at the same time. Each cell is typically sized about 10 square miles. Cells are normally shape like hexagons. Each cell phone has a base station and it consists of a tower and a small building containing the radio equipment. A cell phone carrier gets 832 radio frequencies to use in a city. One city cell can accommodate 56 cellular users at one time. Most cell phones have two signal strengths 0.6 watts and 3.0 watts. The cell phones and base stations are both low power transmitters (Brain, 1998-2002).
?Low power transmitters have two advantages: 1. The transmissions of the base stations and the phones within its cell do no make it very...