Each mobile uses a separate, temporary radio channel to talk to the cell site. The cell site talks to many mobiles at once, using one channel per mobile. Channels use a pair of frequencies for communication one frequency (the forward link) for transmitting from the cell site and one frequency (the reverse link) for the cell site to receive calls from the users. Radio energy dissipates over distance, so mobiles must stay near the base station to maintain communications. The basic structure of mobile networks includes telephone systems and radio services. Where mobile radio service operates in a closed network and has no access to the telephone system, mobile telephone service allows interconnection to the telephone network.
Cell phones, also known as mobile phones or wireless phones, are hand-held phones with built-in antennas. Unlike home phones, cell phones can be carried from place to place with a minimum of fuss. This makes them a good choice for people who want to be in touch with other people even when they are away from the house.
How Do Cell Phones Work?
Not many people know it, but cell phones are actually two-way radios, much like the walkie-talkies of the past, albeit much more advanced. When you talk into your cell phone receiver, it registers your voice and converts the sound into radio waves. These waves travel through the air until they reach a receiver, which is usually found at a base station. This station will then send your call through a telephone network until it contacts the person you wish to speak with. Similarly, when someone places a call to your cell phone, the signal travels through the telephone network until it reaches a station near you. The station sends the radio waves out into the neighboring areas. These radio waves are then picked up by your cell phone and converted into the sound of a human voice.
Cell phones are a vast improvement over
References: 1. Basic Communication Engineering by Rusnani Arifin, Juliana Md Sharif, Nor Hidayah Saad and Mohd Aminuddin Murad. 2. http://www.gsmfavorites.com/documents/introduction/gsm/ 3. en.wikipedia.org/wiki/History_of_mobile_phones