Mobile Telecommunication Networks
Cellular Mobile Telephone Networks

Mobile phones connection can be enabled by radio telecommunication resources and their operation usually follows the operation of fixed telephone networks. The final assembly consists of:

- framework of fixed BS (Base Station)
- MS terminals (Mobile Station)

One of the most fundamental principles applied in modern mobile telecommunication systems is based on dividing of the operated territory into partial elemental areas called as cells, which are always served by a particular base station.

The size of cells used in various mobile systems depends primarily on the type and purpose of the mobile system and can be classified as follows:

- femtocell (flats or offices) - intended for cover areas with low quality of signal from other cells, usually supposed to be indoor with radius of several meters.
- picocell (office and residential environment) - signal range is from tens up to few tens of meters.
- microcell (urban areas with dense housing) - focused mainly to the slower moving participants (for example to a car in city traffic or pedestrians), coverage within a single cell is up to few hundreds of meters.
- macrocells (large and sparsely populated areas) - primarily oriented for the high speed moving participants (for example, vehicles on the roads), diameter of the macrocells is maximally up to few kilometres.
- satellite cell (area accessible by telecommunications satellite) - allows the connection in locations inaccessible for the previous cell types, signal range is dependent on the position of satellites, respectively on their orbit and the parameters of the transmitting and receiving device.

Distribution of operated territory into cells

Cellular structure of the GSM network is usually created by using macrocells with a diameter of up to few kilometres. Example of radio coverage of the territory based on the cellular principle is shown in previous figure. For cellular mobile network structure, a frequency planning is necessary. Frequency plan is working with three or seven frequencies. The same frequencies (f1 to f3, or f1 to f7) can be used in any cluster. The area of all three or seven cells cluster is approximately equal to the average interference zone.