Afar AR24027, Руководство оператора

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AR24027 Operator’s Manual
6-6
Figure 6.2 - Antenna Height and Radio Horizon Graph
6.3.3 Antenna Orientation
Antennas at each end of a communications link must be mounted similarly in terms of polarity, and
directional antennas must be carefully oriented towards each other. The choice of polarization –
horizontal vs. vertical – is in many cases arbitrary. However, interfering signals from such devices as
cellular phones and pagers are generally polarized vertically, and an excellent means of reducing their
effect is to mount system antennas for horizontal polarization.
Orientation of directional antennas is critical because their sensitivity is greatly reduced outside a
fairly narrow angle. Performance of the system can be seriously degraded by mis-aligned directional
antennas. The
AR24027 has a built in feature that allows the operator to use an audio signal to assist
in aligning the antenna. Refer to chapter 5 on the use of this built-in antenna alignment feature.