User's Manual

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To address the primary aims the Spectrum Management algorithm implements a radar
detection function which looks for impulsive interference on the active channel only. If
impulsive interference is detected Spectrum Management will mark the current active channel
as having detected radar and initiate a channel hop to an available channel. The previous
active channel will remain in the radar detected state for thirty minutes after the last impulsive
interference pulse was detected. After the thirty minutes have expired the channel will be
returned to the available channel pool.
The radar detection algorithm will always scan the active channel for 60 seconds for radar
interference before using the channel. This compulsory channel scan will mean that there is a
60 seconds service outage every time radar is detected and that the installation time is
extended by 60 seconds even if there is found to be no radar on the channel.
NOTE: On system installation or start-up this extends the initial scan time of the Master unit
by 60 seconds. To address the “provide aggregate uniform loading of the spectrum across all
devices” requirement, the channel selection algorithm will choose a channel at random from a
list of available channels. The channel selection algorithm is initiated at link initialization and
when radar interference is detected.