Afar AR24027, Руководство оператора

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AR24027 Operator’s Manual
3-6
3.2.4 Antenna Installation
NOTICE
The antennas for the AR24027 must be professionally installed on permanent structures for outdoor
operations. The installer is responsible for ensuring that the limits imposed by the applicable
regulatory agency (Federal Communications Commission, FCC, or CE) with regard to Maximum
Effective Isotropic Radiated Power (EIRP) and Maximum Permissible Exposure (MPE) are not
violated. These limits are described in the following sections.
The AR24027 is typically attached to a pole (with the clamp provided) with the antenna connectors
facing up. For optimum performance the radio must be mounted in close proximity to the antenna
with a cable run typically under 2 meters (6 feet). For the
AR24027 , AFAR Communications Inc.
provides the three antenna types listed below:
Antenna Type Gain AFAR Model Number
Omnidirectional 9 dBi ATO-2409
Panel 18 dBi ATD-2418
Dish Reflector 24 dBi ATD-2424
Antennas at each end of the link must be mounted such that they have the same polarization, and
directional antennas must be carefully oriented towards each other. The choice of polarization
(horizontal vs. vertical) is, in many cases, arbitrary. However, many potentially interfering signals
are polarized vertically and an excellent means of reducing their effect is to mount the system
antennas for horizontal polarization. Of those antennas listed above, the two directional antennas can
be mounted for horizontal or vertical polarization, while the omnidirectional antenna can only be
mounted for vertical polarization.
Proper grounding of the antenna is important for lightning protection as well as to prevent electrical
noise interference from other sources. The antenna should be mounted to a mast or tower that is well
grounded to Earth. Use threaded connectors to mate to the antenna lead connectors and check that all
connectors are clean and tight. Use weatherproof connectors in all outdoor couplings. Also use the
“coax-seal tape” (included with the radio) to further weatherproof outdoor connections.
In locations where it is warranted, you may also want to install a lightning arrestor device at the N
type connector of the radio leading to the antenna (Afar part no SUP-0201). This is particularly
recommended if the coaxial cable between the radio and antenna is of considerable length (greater
than 2 meters or 6 ft).