Outdoor Antenna Installation Guide 3-1
3
Determining Range &
Clearance
The Fresnel Zone 3
As identified in
Chapter 2 - Installation Guidelines
, you need a
clear line-of-sight to set up an outdoor antenna installation that
meets your requirements in terms of range and throughput
performance.
In Chapter 2, we described the shape of the radio beam (Fresnel
Zone) as being bulged in the middle. The exact shape and width of
the Fresnel Zone is determined by the path length and frequency
of the radio signal.
If any significant part of the Fresnel Zone is obstructed, a portion of
radio energy is lost, resulting in reduced performance. For optimal
performance, you must ensure that the antenna products you
choose, in combination with the height of the antenna installation
above ground, will provide sufficient clearance to allow your
antenna installation to cover the distance between the two wireless
sites.
NOTE
A
wireless outdoor antenna connection that lacks sufficient
clearance will suffer from poor performance. When radio
performance is poor, the network response is poor as well,
due to many retransmission attempts of lost data frames.
