Afar AR-24010E, Руководство оператора

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pulsAR radio Operator's Manual
Band Antenna Type Gain AFAR Model Number
900 MHz
Omni-directional 5 dBi ATO-0905
Dish Reflector 15 dBi ATD-0915
2.4 GHz
Omni-directional 9 dBi ATO-2409
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 directional antennas can be
mounted for horizontal or vertical polarization, while the omni-directional antennas 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 weatherproof connectors in all outdoor couplings. Also use the “coax-seal
tape” (included with the radio) to further weatherproof outdoor connections.
The radio antenna ports come equipped with a quarter-wave short to ground which provides adequate
surge protection of the RF front-end circuitry when you install the radio close to the antenna using a
coaxial cable of less than 10 ft (3 m). If the coaxial cable between the radio and antenna exceeds that
length you may also want to install a lightning arrestor device at the N type connector of the radio
(Afar part no SUP-0205).
3.2.5 Antenna Alignment
When mounting the high gain antenna (24 dBi), the proper antenna alignment is extremely important
since the beam-width of the antenna is very narrow. Once you perform a rough alignment and the
link is in operation, you can use the “monitor-link” and “antenna-alignment-aid” commands. Type:
> monitor-link
in order to update, every half second, the link statistics including the RSSI level. The antenna can
then be aligned so that the RSSI is maximized. In the PmP topology, the hub antenna is typically an
omni and dose not need to be carefully aligned. But if you need to align a hub radio antenna for
maximum signal from a particular remote use the command:
> monitor-link node=N
where N identifies the remote per the table displayed with the show command
Since in many applications the antenna is on a tower where it is not practical to have a terminal
nearby, the
pulsAR radio provides an “antenna alignment aid” available at the outdoor unit. This
feature uses the three pin “Auxiliary port” connector to output an audio signal with a pitch
proportional to the receive signal strength. AFAR provides a special cable adapter that converts the
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