Alvarion BreezeACCESS II, Системное руководство

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Indoor SU-I and AU-I Units
3-5
BreezeACCESS Version 4.5 System Manual
capabilities. By using two antennas per unit, the system can select the
best antenna on a per-packet basis (every several milliseconds).
When installing a single antenna, configure the Transmit Antenna
option to either Antenna 1 or Antenna 2 , according to the antenna
being used. When using two antennas, configure the Transmit
Antenna option to Both Antennas .
Antenna Polarization
Antenna polarization must be the same at either end of the link. In most
applications, the preferred orientation is vertical polarization. Above
ground propagation of the signal is better when it is polarized vertically.
For omni antennas, make sure that the antennas are extended upward
vertically in relation to the floor to achieve vertical polarization. To verify
polarization of detached antennas, refer to the assembly instructions
supplied with the antenna set.
Antenna Seal
When using outdoor antennas, you must seal the antenna connectors
against rain. Otherwise the antennas are not suitable for use in outdoor
installations.
Lightning Protection
Lightning protection is designed to protect people, property and
equipment by providing a path to ground for the lightning’s energy. The
lightning arrestor diverts the strike energy to the ground along a
deliberate and controlled path instead of allowing it to choose a random
path. Lightning protection for a building is more forgiving than
protection of electronic devices. A building can withstand up to 100,000
volts, but electronic equipment may be damaged by just a few volts.
Lightning protection entails connecting an antenna discharge unit (also
called an arrestor) to each cable as close as possible to the point where
it enters the building. It also entails proper grounding of the arrestors
and of the antenna mast (if the antenna is connected to one).
The lightning arrestor should be installed and grounded at the point
where the cable enters the building. The arrestor is connected to the
unit at one end and to the antenna at the other end.
The professional installer you choose must be knowledgeable about
lightning protection. The installer must install the lightning protector in
a way that maximizes lightning protection.
AL 1 Lightning Arrestor - Part No. 872905 5 ft (1.5m), “N” Male to “N”
Female is available from Alvarion.