Ubiquiti Networks airFibe5 - Manual

D
esign Guide
Getting the Most from a
Versatile Platform
The airFiber AF24 is a versatile platform that can be optimized
for a variety of conditions. The user interface is simple and
intuitive, but there are numerous configuration parameters.
The AF24 is a veritable Swiss Army knife when it comes to
versatility and options to address different needs.
airFiber Configuration Interface
Configuration for Ultimate Speed and
Latency Performance
Typically the best speed and lowest latency will be obtained
with the AF24 configured as a full-duplex system using
Frequency Division Duplexing (FDD). The data streams
generated by the AF24 are simultaneously transferred
across the wireless link. The transmitter and receiver are
running concurrently in time. Because of the trade-off
between bandwidth resources and propagation conditions,
this approach is typically reserved for links in areas where
installations are in clear line-of-sight conditions and free of
reflected energy such as that generated by heavy rain or
intermediate objects. Installations that are subject to Fresnel
reflections or highly scattered environments may experience
some level of degradation at great range.
For Full Duplex mode, the TX and RX Frequencies should be
different.
TX
RX
TX
RX
Slave Master
Frequenc
y A Frequenc
y B
Full-Duplex Diagram
Configuration for Highest Possible
Availability and Robustness
Links that are installed in environments that are highly
reflective or subject to considerable scattering due to heavy
rain or foliage loss are typically better suited to half-duplex
configurations. In this case the frequency and bandwidth
resources are shared on a Time Division Duplexing (TDD)
basis, and the system can accept higher levels of propagation
distortion. The trade-offs are reduced throughput and slightly
higher latency.
For Half Duplex mode (default), the TX and RX Frequencies can
be the same or different to suit local interference.
TX
RX
TX
RX
Slave Master
Frequenc
y A Frequenc
y A
Half-Duplex Diagram
The AF24 radio system has the ability to manage time and
bandwidth resources, similar to other systems utilizing
different modulation schemes that are scaled according
to the noise, interference, and quality of the propagation
channel. The AF24 system also automatically scales its
modulation based on channel quality but has the ability to be
reconfigured from a time/bandwidth perspective to allow for
best possible performance. In many regards the suitability of
the duplexing scheme needs to be taken into account based
on the ultimate goals of the user. Just as channel conditions
have an effect on the modulation scheme selection, there are
effects on duplexing modes to consider as well.
Design Guide