User's Manual

Planning and Installing Wireless LANs
BreezeNET PRO.11 Series 4-13 User’s Guide
4.2. Outdoor Installation Considerations
This chapter describes various considerations to take into account when
planning an outdoor installation including site selection, antenna alignment,
antenna diversity, antenna polarization, antenna seal, and cell size.
4.2.1. Site Selection Factors
When selecting a location for external antennas, remember to take into
consideration the following guidelines:
• Minimum distance between sites
• Maximum height above the ground
• Maximum line of sight clearance
• Maximum separation between antennas (diversity option)
Path of Clearest Propagation
A propagation path is the path that signals traverse between the antennas of
any two bridges. The “line” between two antenna sites is an imaginary
straight line which may be drawn between the two antennas. Any obstacles
in the path of the “line” degrade the propagation path. The best propagation
path is, therefore, a clear line of sight with good clearance between the
“line” and any physical obstacle.
Physical Obstacles
Any physical object in the path between two bridges can cause signal
attenuation. Common obstructions are buildings and trees. If a bridge’s
antenna is installed indoors, the walls and/or windows between the two sites
are physical obstructions. If the antenna is positioned outdoors, any
buildings or other physical structure such as trees, mountains or other
natural geographic features higher than the antenna and situated in the path
between the two sites can constitute obstructions.
Install indoor antennas as close as possible to a window (or wall if a
window is not accessible) facing the required direction. Avoid metal
obstacles such as metal window frames or metal film anti-glare windows in
the transmission path. Install outdoor antennas high enough to avoid any
obstacles which may block the signal.