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Radio waves: Transport medium for words and data

For wireless information exchange, you need mobile phones and base stations (antennae). They exchange digitalised signals – words or data have first been converted into these digital signals. For this, they use the only available transport medium: high-frequency electromagnetic fields (radio waves, also called "rays" in everyday language). As the distance to the source increases, these radio waves not only lose their intensity, they also come across obstacles – natural (e.g. mountains, rain) or man-made (such as buildings). They are then either reflected, absorbed, bent or broken. These effects must be taken into account while planning the original transmission capacity of an antenna.

Cells form a honeycombed network

Each base station defines its own wireless cell. It can have a diameter of a few hundred metres in cities to a few kilometres in rural areas. All cells arranged next to each together in the honeycomb form the mobile communication network.

Load determines network size and technology

Each base station can only exchange a limited number of signals. At locations with high volumes of voice and data traffic, the antennae have to be fairly close to each other and the network should be of smaller cells. Capacities required at a particular location may also affect the technology that is used (GSM, GPRS, UMTS, EDGE).

Construction of a cellular mobile communication network