Antennas play a very important part in a communications system,
coupling energy between a transmitter or receiver and the propagation
medium. While an antenna can be as simple as a
piece of wire, more suitable antenna designs are available. Matching
the correct antenna to the set ensures maximum radiated power.
In practice, different designs suit different applications, which has led
to the design and development of a great many different
types of antenna.
An antenna ideally has the following characteristics
(particularly when deployed as part of a mobile communications system):
Directionality and gain. A compromise must be made between saving
transmitter power (having high gain) and requiring high alignment accuracy
or directionality (difficult to achieve in the field).
Bandwidth. The antenna
should preferably not require readjustment when the frequency is changed
(within limits of course).
Low sidelobes. The radiation pattern should have
limited power in other than the desired direction to limit
eavesdropping, direction finding, jamming and mutual interference.
Size. Antennas should be
small and robust for ease of handling.
A base station antenna
can be either:
an omni antenna
a sectoring antenna
Other topics in our resources on GSM related to GSM Base Station Antenna include: