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design is of course based on the empirical rain and multipath fading models for the average worst month.
No real guarantee for the availability due to weather conditions can be given, but statistically the designed
hops will meet the targets.
A more expensive solution would be to design the hop for 99,999% availability for the full 256QAM 366
Mbit/s. This would mean using larger antennas and/or shorter hop lengths (i.e. additional CAPEX). The
adaptive modulation would then ensure that high priority traffic at lower capacity would have much better
availability.
It is crucial that the hop attenuation after aligning the antenna is correct when compared to the fade
margin calculation. If the designed fade margin is not available, the availability for the various traffic
classes cannot be achieved.