Sure, it’s possible, DFS is a stupid scheme for anything that needs to be 
reliable.  On the other hand, only the AP does radar detection, not the CPE, so 
a customer router near the CPE shouldn’t trigger a false DFS event.  And if you 
have the antenna gain properly configured on the AP, the radar detection level 
should be relatively high, so that a customer router a mile away through an 
outer wall shouldn’t trip it.  If you have a rooftop AP, or houses right near 
the tower, it could happen.  Also I believe we have seen atmospheric conditions 
create false DFS events probably by ducting the signal from a transmitter we 
usually can’t see.  I also suspect reflections off metal objects like trucks, 
trains, maybe even airplanes can cause events.



From: Af [] On Behalf Of Eric Muehleisen
Sent: Friday, October 14, 2016 10:50 AM
Subject: [AFMUG] DFS impact on indoor SOHO routers


On occasion we see DFS events on our outdoor WISP network. It's rare, but does 
happen. It's understandable since we use high gain sector antennas and AP's 
with great receive sensitivity. Not to mention these are outdoor radios with 
direct view of the sky.


On the other hand, we are seeing 802.11ac home routers with DFS capabilities. 
The router indoors has all sort of built in attenuation, walls, obstacles, etc. 
Would you expect to see DFS events, if any, in this scenario?



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