Programming instructions

2-6
BreezeNET DS.5800 System Manual
Manual Revision: 1.0
! 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.
Rooftop Installation
Rooftop installations offer several advantages:
! Fewer obstacles in the path.
! Improved performance due to greater height.
Antennas for Outdoor Applications
The BreezeNET DS.5800 series can be used in point-to-point or point-
to-multipoint configurations.
Point-to-Point
The BU-DS.5800/RB-DS.5800 can be equipped with a directional
antenna. The required antenna gain depends on the required range and
performance.
Using the 28dBi 2 ft. parabolic antennas available from Alvarion,
distances of up to 30 miles (50 km) can be achieved.
Point-to-Multipoint
Setting up a point-to-multipoint link requires the use of a base unit
equipped with an omni-directional antenna (or an antenna with
sufficient beamwidth to illuminate all units) and at least two remote
units equipped with high-gain directional antennas.
Antenna Polarization
Antenna polarization must be the same at both ends of the link. In most
applications, the preferred orientation is vertical polarization, which is
best for above ground propagation. To verify antenna polarization, refer
to the assembly instructions supplied with the antenna set.
Antenna Seal
When using outdoor antennas, you must seal all cable connections to
prevent water or dirt from entering the connector.