4RF Aprisa XE, Руководство пользователя

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Antenna alignment
For any point-to-point link, it is important to correctly align the antennas to maximize the signal
strength at both ends of the link. Each antenna must be pointing directly at the corresponding antenna
at the remote site, and they must both be on the same polarization. The antennas are aligned visually,
and then small adjustments are made while the link is operating to maximize the received signal.
Directional antennas have a radiation pattern that is most sensitive in front of the antenna, in line with
the main lobe of the radiation pattern. There are several other lobes (side lobes) that are not as
sensitive as the main lobe in front of the antenna.
For the link to operate reliably, it is important that the main lobes of both antennas are aligned. If any
of the side lobes are aligned to the opposite antenna, the received signal strength of both terminals will
be lower, which could result in fading. If in doubt, check the radiation patterns of the antennas you are
using.
Checking the antenna polarization
Check that the polarization of the antennas at each end of the link is the same.
Antenna polarization of grid antennas are normally indicated by an arrow or with “H” and “V” markers
(indicating horizontal and vertical).
On Yagi antennas, ensure the orientation of the elements are the same at each end of the link.
Transmit frequency and power, and antenna polarization would normally be defined by a regulatory
body, and typically licensed to a particular user. Refer to your license details when setting the antenna
polarization.