Airspan AS3010, Hardware Installation Manual

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Radio Site Plannin g Hardw are Insta llatio n Guide
5-2 Airspan Networks Inc. 02030311-10
5.1. Minimal Radio Path Obstructions
ASWipLL radios communicate by propagation of waves. Thus, ensure minimum
obstructions (from, e.g. buildings and trees) in the radio path between Base Station
radio (i.e. BSR) and subscriber radios (i.e. SPR/IDR). It is essential that the
ASWipLL radios or antennas be installed in such a way that their radio paths have a
clear path with each other.
5.2. Fresnel Zone Clearance
There must be sufficient open space around the radio path to minimize interference
with the radio beam. A minimum of
60% of the first Fresnel Zone of the path
should be clear of obstructions. Despite a clear line-of-sight, objects close enough to
the transmission path may cause attenuation in signal strength and an increase in
signal interference. Objects with reflective surfaces that seem relatively far away,
but yet still encroaching on Fresnel Zone, may cause these interferences.
Figure 5-1: At least 60% of first Fresznel Zone should be clear