User's Manual Part 1

Release8PlanningGuide
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Issue2,November2007 Draft5forRegulatoryReview 145
• whether you will have collaborative rights and veto power to prevent interference
to your equipment from wireless equipment that is installed at the site in the
future.
• whether a pre-existing grounding system (path to Protective Earth
) exists, and
what is required to establish a path to it.
• who is permitted to run any indoor lengths of cable.
12.6.3 AssuringtheEssentials
In the 2.4-, 5.2-, 5.4-, and 5.7-GHz frequency band ranges, an unobstructed line of sight
(LOS) must exist and be maintainable between the radios that are involved in each link.
Line of Sight (LOS) Link
In these ranges, a line of sight link is both
• an unobstructed straight line from radio to radio.
• an unobstructed zone surrounding that straight line.
Fresnel Zone Clearance
An unobstructed line of sight is important, but is not the only determinant of adequate
placement. Even where the path has a clear line of sight, obstructions such as terrain,
vegetation, metal roofs, or cars may penetrate the Fresnel zone and cause signal loss.
Figure 33 illustrates an ideal Fresnel zone.
Transmitter
or Amplifier
receiver
transmitter
Fresnel zone
Figure 33: Fresnel zone
FresnelZoneCalcPage.xls
calculates the Fresnel zone clearance that is required between
the visual line of sight and the top of an obstruction that would protrude into the link path.
Non-Line of Sight (NLOS) Link
The Cyclone 900-MHz modules have a line of sight (LOS) range of 40 miles (more than
64 km) and greater non-line of sight (NLOS) range than Cyclone modules of other
frequency bands. NLOS range depends on RF considerations such as foliage,
topography, obstructions.
12.6.4 FindingtheExpectedCoverageArea
The transmitted beam in the vertical dimension covers more area beyond than in front of
the beam center.
BeamwidthRadiiCalcPage.xls calculates the radii of the beam coverage
area.