A mobile network, also referred to as a cellular network, employs the use of radio frequencies that can be used simultaneously by several callers at one and the same time. Cell-sites and mobile devices manipulate the frequency, so that they can make use of low-power transmitters to supply their services with the least possible interference.
Mobile carriers use these mobile networks to offer wide network coverage to their subscribers. Larger regions are split up into smaller cells, all of which are connected to telephone switches or telephone exchanges, which again help in public telecommunication while on the move.
Different types of mobile technologies are used to provide mobile network services to users. Most common among them are GSM (Global System for Mobile Communication), GPRS (General Packet Radio Service), CDMA (Code Division Multiple Access), EDGE (Enhanced Data Rates for GSM Evolution), iDEN (Integrated Digital Enhanced Network) and EV-DO (Evolution-Data Optimized).
The signal reception and/or call service quality may be subject to change, depending upon the current location and region of the user. Some of the leading mobile network providers in the United States of America are Verizon Wireless, AT&T, T-Mobile and Sprint Nextel.
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