A cellular network or mobile network is a radio network distributed over land areas called cells, each served by at least one fixed-location transceiver, known as a cell site or base station. In a cellular network, each cell uses a different set of frequencies from neighboring cells, to avoid interference and provide guaranteed bandwidth within each cell.
When joined together these cells provide radio coverage over a wide geographic area. This enables a large number of portable transceivers (e.g., mobile phones, pagers, etc.) to communicate with each other and with fixed transceivers and telephones anywhere in the network, via base stations, even if some of the transceivers are moving through more than one cell during transmission.
Cellular networks offer a number of advantages over alternative solutions:
- flexible enough to use the features and functions of almost all public and private networks
- increased capacity
- reduced power use
- larger coverage area
- reduced interference from other signals
An example of a simple non-telephone cellular system is an old taxi drivers' radio system, in which a taxi company has several transmitters based around a city that can communicate directly with each other.
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