Because of differences in component configuration, placement, and physical
environment, every infrastructure application is a unique installation. Before
installing the system, a site survey should be performed in order to determine
the optimum utilization of networking components and to maximize range,
coverage, and infrastructure performance. Figure
shows some
operating and environmental conditions that need to be considered:
- Data Rates – Coverage is inversely proportional to data bit rates. The
maximum radio range is achieved at the lowest workable data rate. There will be
a decrease in receiver threshold as the radio data rate increases.
- Antenna Type and Placement – Proper antenna selection and installation is a
critical factor in maximizing radio range. As a general guide, range increases
in proportion to antenna height and gain.
- Physical Environments – Clear or open areas provide better radio range than
closed or filled areas.
- Obstructions – A physical obstruction such as shelving or a pillar can
hinder the coverage of the wireless system. Avoid locating the computing device
and antenna in a location where there is a barrier between the sending and
receiving antennas.
- Building Materials – Radio penetration is greatly influenced by the
building material used in construction. For example, drywall construction
allows greater range than concrete blocks.
- Line of Sight – A clear line of sight must be maintained between wireless
bridge antennas. Any obstructions may impede the performance or prohibit the
ability of the wireless bridge to transmit and receive data. Directional
antennas should be placed at both ends at the appropriate elevation with
maximum path clearance.