A solid parabolic dish can allow WLANs to operate over long distances. It
has a narrow beamwidth, and depending on the speed and gain of the antenna
used, distances of up to 40 km (25 miles) may be possible. It is important to
evaluate how well the dish will withstand icy conditions and high winds.
Equally important is the sturdiness of the mast and tower the antenna will be
mounted on.
The Cisco high gain parabolic dish is designed to be used as
a bridge antenna between two networks or for point-to-point communications
. It consists of
an aluminum parabolic reflector and feed antenna. The antenna features a rugged
mount. It also offers 20 degree fine adjustment for both horizontal and
vertical planes. The antenna is provided with hardware for mast mounting. The
dimensions are shown in Figure
. The
radiation pattern is shown in Figure
.
The 5 GHz
28-dBi dish antenna is a non-diversity parabolic antenna which operates in the
UNII-3 band (5725 to 5825 MHz)
. The antenna is
designed to be mounted outdoors on a mast. The antenna is also designed to be
used at either or both sides of a point-to-point installation or the non-root
side of a point-to-multipoint installation. The radiation patterns are shown in
Figures
and
. When the
antenna is used at both sites, point-to-point line-of-sight (LOS) range can be
extended up to 12.9 miles (20.7 kilometers) at 54 Mbps. When the antenna is
used at a client site and a 10-dBi sector antenna is used at the hub site,
point-to-multipoint LOS range can be extended up to 3.8 miles (6.1 kilometers)
at 54 Mbps.