Cisco Cisco Aironet 1400 Wireless Bridge Guía De Instalación
5
Cisco Aironet 1400 Series Wireless Bridge Mounting Instructions
OL-7618-01
Physical Site Inspection
A tree directly in the path can totally block the signal. With clearance above the trees there are
usually no secondary effects, but you should allow for future tree growth.
usually no secondary effects, but you should allow for future tree growth.
•
Man-made obstacles
A large round container such as a gas storage reservoir or water tower that is partially in the path
causes some blocking. These obstacles may also reflect some energy, which can interfere with other
receivers. Square or rectangular objects in or near the path have rectangular surfaces that can block
and diffract signals over and around them.
causes some blocking. These obstacles may also reflect some energy, which can interfere with other
receivers. Square or rectangular objects in or near the path have rectangular surfaces that can block
and diffract signals over and around them.
•
Earth surface
The earth surface also interferes with signals if the antenna is mounted to low. Mount the antenna
just high enough to allow adequate clearance from the ground (see
just high enough to allow adequate clearance from the ground (see
). Placing the bridge too
high makes it susceptible to interference from other systems.
To determine how much clearance to leave around the signal path, use the following clearances as a
guide:
guide:
Install the bridge or external antenna where obstacles along the propagation path, including the ground,
are no closer than these values. For tower installations, you may need to climb the tower to the proposed
mounting location to verify a clear path to the other site. If trees are in the line of signal propagation,
leave extra clearance around them for future growth into the signal path and seasonal changes.
are no closer than these values. For tower installations, you may need to climb the tower to the proposed
mounting location to verify a clear path to the other site. If trees are in the line of signal propagation,
leave extra clearance around them for future growth into the signal path and seasonal changes.
Physical Site Inspection
Perform a visual inspection of the site to ascertain and document the physical characteristics of the site
and to ensure that all requirements are met for the proper installation and operation of the system.
and to ensure that all requirements are met for the proper installation and operation of the system.
Contact Information and Access Permissions
Make sure the following general issues are resolved before beginning the installation:
•
Validate customer-provided information, such as site contact names and telephone numbers.
•
Examine the building (tenant) lease to verify or establish building roof or tower rights. If available,
use layout drawings to evaluate the feasibility of modifications or special permits that might be
necessary.
use layout drawings to evaluate the feasibility of modifications or special permits that might be
necessary.
•
For a tower-mounted installation, determine if the owner, operator, or landlord requires a
professional or certified tower climber to do the work.
professional or certified tower climber to do the work.
Table 1
Clearance Guidelines for UNII 5.7-GHz Frequencies
Total Path Length (Miles)
Clearance Radius Around Signal Path (feet)
4
30
6
37
8
42
10
47
12
52
15
58