Cell Phones :: essays research papers

Digital boothphonephone phone from Nokia Millions of people in the United States and around the world use cellular phones. They are much(prenominal) smashing gadgets -- with a cell phone, you can talk to anyone on the satellite from just about anywhere These days, cell phones provide an incredible roll of functions, and new ones are being added at a breakneck pace. Depending on the cell-phone model, you can Store contact information Make task or to-do lists Keep track of appointments and set reminders Use the built-in calculator for simple math Send or receive e-mail concentrate information (news, entertainment, stock quotes) from the Internet Play simple games Integrate a nonher(prenominal) devices such as PDAs, MP3 players and GPS receivers But have you ever wondered how a cell phone works? What makes it different from a regular phone? What do all those confusing terms like PCS, GSM, CDMA and TDMA mean? In this article, we pass on discuss the technology behind cell phon es so that you can compute how amazing they really are. If you are thinking about buying a cell phone, be sure to check out How Buying a Cell Phone Works to learn about everything you should know forward making a purchase. Lets start with the basics In essence, a cell phone is a radio. One of the most interesting things about a cell phone is that it is actually a radio -- an extremely educate radio, but a radio nonetheless. The telephone was invented by Alexander graham Bell in 1876, and wireless communication can trace its grow to the invention of the radio by Nikolai Tesla in the 1880s (formally presented in 1894 by a young Italian named Guglielmo Marconi). It was only natural that these two great technologies would eventually be combined In the dark ages before cell phones, people who really needed mobile-communications ability installed radio telephones in their cars. In the radio-telephone system, there was one central antenna tower per city, and perhaps 25 channels avail able on that tower. This central antenna meant that the phone in your car needed a powerful transmitter -- big abundant to transmit 40 or 50 miles (about 70 km). It also meant that not many people could use radio telephones -- there just were not enough channels. The genius of the cellular system is the division of a city into small cells. This allows extensive frequency reuse across a city, so that millions of people can use cell phones simultaneously.