Solectek SkyMate, Operator'S Manual, Page: 114 / 124

Appendix C: Glossary and Basic Concepts
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• Reduce the strength of second Fresnel zone reflections, thus reducing the
potential for interference.
• Reduce interference from other RF devices within the same frequency
range at distances closer than the target antenna.
Multidirectional. Multidirectional antennas are used for connections where
several interfacing antennas are located in the same general direction. To achieve
directionality with a 2.4 GHz system, Solectek uses an antenna with a sectoral.
Because multidirectional antennas have a more focused beam than
omnidirectional antennas, they achieve higher gain and have greater spanning
distances.
Omnidirectional. Omnidirectional antennas are used for connections where the
interfacing antennas are located in opposing directions. Because the focus of an
omnidirectional antenna is 360 degrees, it has less gain and spans a smaller
distance than other types of antennas.
Antenna Alignment
Antenna Polarization. To improve the isolation between adjacent antenna
installations, in addition to using different channels, you can change polarization.
Consult your Solectek systems engineer for specific details.
Fresnel Zones. Waves can be deflected by objects in their paths. If a wave from
an outer band of the cone (see Radio Signals) is deflected back through the center
lobe, it can either strengthen that signal or reduce its strength, depending on how
the waves align when they collide. A glancing deflection changes the angle of the
wave very little, so it remains generally in phase with the wave at the center lobe.
Within the signal span, there are zones where deflected signals are generally in
phase with the center lobe signal, and there are other zones where deflected signals
are generally out of phase with the center lobe signal. We refer to these zones as
Fresnel (frËnl) zones.
The first Fresnel zone surrounds the center lobe where the RF signal is strongest.
If more than 40% of the first Fresnel zone is obstructed, your RF line of sight is