Ubiquiti Networks airFibe5 User Manual
Design guide: airfiber af5/af5u, Selection of installation site
DESIGN GUIDE:
airFiber AF5/AF5U
Best Practices for Installation of the airFiber AF5/AF5U
Ideal Mounting Location: High in Elevation with
Clear Line of Sight
Custom Frequency and Transmit Power
Configuration to Fit Your Application
Throughout Optimization with Maximum
Frequency Reuse and Link Symmetry
Selection of Installation Site
The airFiber® AF5/AF5U, referred to as the AF5 in this Design
Guide, features unique functionality that requires you to be
cognizant of the installation environment.
For best performance, you must install the AF5 as high up
as possible, with a line of sight free from obstructions. This is
especially true in FDD (Frequency Division Duplexing) mode,
as there is a requirement to maximize channel/spectrum reuse.
Any objects in front of or near the front of the AF5 can have a
significant impact on overall performance. The AF5 should be
installed 1 m (3.3 ft) below the highest point of the structure
to reduce the risk of a lightning strike. When the AF5 must be
installed above a metallic surface like a corrugated flat roof or
water tower, then you should ensure that the AF5 is located
more than 3 m (10 feet) above the metal/reflective surface.
3 m (10 ft)
Good Location
1 m (3.3 ft)
Close-up of Installation on Top of Water Tower
What is generally true for cellular installations is true for the
AF5. You should mount the AF5 where it can see no reflections
in the near field, so we recommend the following types of
mounting sites:
§
Perimeter mounting on a water tower/structure (best)
§
Mounting near the edge of the top of a structure
§
Mounting on an elevated mast or tower
Radios that are mounted anywhere near the surface of a
roof or the top of a water tower can be significantly affected
by reflections. FDD is more susceptible to the elements
of a deployment environment than TDD (Time Division
Duplexing) is.
Best Location
Bad Location:
Reflection off Rooftop
and Lip of Building
Close-up of Installation on Rooftop of Building
Good and bad examples of deployments are depicted in this
section, “