The installation of the radiant system or antennas at each base station in a radiocommunications network is decisive for its performance.
There are several types of antennas, and it is important to distinguish how the energy transmitted or received by the antenna is directed.
It is usual to distinguish between two modes of antenna radiation: omnidirectional and directional.
In the first case, the antenna radiates in all directions with the same radio signal intensity, whereas, in the second case, radiation is focused in certain directions.
In general, antennas have a slight vertical inclination, which gives the principal radiation beam a slight downward inclination.
Antennas are used in all radiocommunication services (radio and television stations, communication systems for police and fire services, mobile phones, etc.). The choice of antenna depends on the type of service provided. In the case of mobile phones, base station antennas are often direction and installed either on masts or on buildings, in sufficient number and with sufficient height to ensure the coverage of a particular service area (cell).
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