User Manual

Planning and Installing Wireless LANs
BreezeNET PRO.11 Series 5-14 User’s Guide
5.2.2. Antennas for Indoor applications
For most indoor applications, the best choice is the standard unit equipped
with its integrated 2dBi antennas. The units are small, easy to install and
cover a large area.
In some installations, it is required to install the unit and antenna separately.
In such instances, use the AP-10D with the omni-6 antenna kit (6dbi omni-
directional antenna with 3 meter RG-58 cable). In the USA (FCC regulated)
and in non-regulated countries, the omni-6 comes with a shorter antenna
cable, extending the coverage area.
The Uni-8.5 is also useful in indoor applications. It is very small and easily
wall-mounted, but its radiation pattern is limited (75°).
BreezeCOM recommends that, for indoor applications, you use two
antennas per unit to utilize the diversity gain of the system.
5.2.2.1 Antenna Diversity
In applications where no multipath propagation is expected, a single antenna
is sufficient to ensure good performance levels. However, in cases where
multipath propagation exists, BreezeCOM recommends that two antennas
be used. This takes advantage of space diversity capabilities. By using two
antennas per unit, the system can select the best antenna on a per-packet
basis (every several milliseconds).
Multipath propagation is to be expected when there are potential reflectors
between the main and remote sites. These reflectors may be buildings or
moving objects such as airplanes and motor vehicles. If this is the case, the
radio signal does not travel in a straight line, but is reflected or deflected off
of the object, creating multiple propagation paths.
When installing a single antenna, modify the transmit diversity option to
either antenna 1 or antenna 2, according to the antenna being used (refer to
section 3.4.3).
5.2.2.2 Antenna Polarization
Antenna polarization must be the same at either end of the link. In most
applications, the preferred orientation is vertical polarization. Above-ground
propagation of the signal is better when it is polarized vertically. To verify
antenna polarization, refer to the assembly instructions supplied with the
antenna set.