Specifications

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Example of Yagi aerial
Antennas
A whip antenna is the most common example of a monopole antenna, an
antenna with a single driven element and a ground plane.
The whip antenna radiate equally in all directions in a horizontal plane, although
they have a conical blind zone directly above them.
A whip antenna is not to be recommended in public installations. It could be
more suitable to mount a more discreet antenna, which is not so easy to break
or to be vandalised (Low prole).
In mobile applications is it suitable to have omni directional antennas (Dipole)
to achieve higher reliable transmission.
If there is a stationary installation and the signal strength is not enough is it pos-
sible to use directional antennas (Yagi). In point-to-point, xed radio networks, it
is always highly recommended to use directional antennas when applicable.
This is because of better control over the system and closed construction; the
signal is forced and noise collected only to and from the relevant directions.
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Radiation patterns for omni directional antennas (left; Dipole) and directional
antennas (right; Yagi).
Example of
Dipole aerial
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Tel : [phone] - Fax : [phone] - Web : http: www.audin.fr - Email : [e-mail]