4.2 Create a Bridge Network Environment
The bridge supports external antennas with omni-directional or directional
capabilities. Omni-directional antennas are suited for systems requiring a signal
distribution in more than one direction. High-gain directional antennas are best suited
for longer coverage range in a fixed direction.
Due to the differences in placement and physical environment, every network
application has their unique installation. Before installing multiple bridges, you
should implement a testing of each site to determine the optimum networking
components and to maximize coverage range and network performance.
Think about the operating and environmental conditions of following when
implement this testing:
•
Throughput of Data – Coverage range is inversely proportional to data rates.
The maximum radio range is achieved at the lowest workable data throughput.
•
Antenna type and placement – The coverage range is increasing by the
antenna’s height and gain. For this reason, proper antenna configuration is a
critical factor in maximizing coverage range. The recommended combination
of antenna/cable/booster for various ranges is as following:
Range
3km 4~10km
11~18km
19~25km
Cable
1M 3/5M 10M 1M 3/5M
10M
1M 3/5M
10M 1M 3/5M
10M
Antenna gain
(dBi)
12 12~18 18 12 12~18
18 12 12~18 18~20 20 12~21 18~21
Booster
None None None 0.5W 0.5W 0.5W
1W
1W
1W 1W 5W
5W
•
Physical environment and Obstructions - Open areas provide better coverage
range than closed areas. Also, the obstructer such as steel buildings or trees
can block or decrease communication between bridges. To avoid this situation,
the antennas should be located in where is no or few obstruction between the
sending and receiving antennas.
Figure 4.2
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