I-O Wireless WBC11, Руководство пользователя

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2.2 Basic Alignment of the Antenna
Due to its directive behavior, an antenna needs to be aligned. Alignment is done
by maximizing the antenna signal and by minimizing phase noise. The phase
noise directly influences bit error rate. The alignment is essential because certain
weather conditions can degrade the signal strength. Also essential to obtaining
the strongest signal is the use of a low noise antenna cable. To avoid link
dropouts with bad weather, the antennas need to receive the strongest signal
possible with the lowest possible phase noise. In most situations a high signal
level means a low bit error rate, but it does not go without saying. In some cases
the lowest Bite Error Rate is reached at a signal strength level that is not the
highest possible.
The bridge has a Radio Signal Strength Indicator (RSSI) and a SQ2 indicator.
These indicators need to be used during alignment. Both indicators are displayed
at the same time.
To be able to read the RSSI and SQ2 the bridge needs to be connected to a
computer via a small hub. This computer needs to be equipped with an Ethernet
card. The set-up depicted in figure 2.3 needs to be made.
NOTE: The bridge unit is equipped with two antenna connectors (1 & 2).
Always use connector 1, Connector 2 is only used in special cases by an
experienced installer. For information about using the second antenna
option, please contact I-O.
Figure 2.3 Interconnection during installation