Rooftop Installation - Alvarion BreezeNET PRO.11 Series User Manual

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.
Path loss is determined mainly by several factors:
Distance between sites – Path loss is lower and system performance better
when distances between sites are shorter.
Clearance – Path loss is minimized when there exists a clear line of sight. The
number, location, size, and makeup of obstacles determine their contribution to
path loss.
Antenna height – Path loss is lower when antennas are positioned higher.
Antenna height is the distance from the imaginary line connecting the antennas
at the two sites to "ground" level. "Ground" level in an open area is the actual
ground. In dense urban areas, "ground" level is the average height of the
buildings between the antenna sites.

5.3.2 Rooftop Installation

Note :
Rooftop installations offer several advantages:
Increased antenna range.
Fewer obstacles in path.
Improved performance due to greater height.
Reduced multipath problems.
BreezeNET PRO.11 Series
Rooftop antenna installations are extremely dangerous! Incorrect installation
may result in death, serious injury and/or damage. Such installations should be
performed by professional antenna installers only!
Planning and Installing Wireless LANS
5-17
User's Guide