Last Post: November 26, 2017:
Just curious if there is a best practice/guideline and/or standard some where talking about the distance from the airport and using DFS channels? Thank you
I have seen recommendations, but cant remember where at the moment.
Google FCC, FAA, and DFS in the same search, and you'll find all sorts of interesting things.
including posts about the fines the FCC has handed out to "naughty" companies using DFS channels.
There is no legal constraint on using DFS channels near an airport as long as the system implements DFS procedures; however, more DFS channel switches are of course likely to occur there. For this reason, many recommend avoiding them if at all possible within a few miles of an airport. But you can test them to see the results you get at your location. Watch your AP management system (controller, cloud, etc.) for DFS events in the logs (you'll need to research vendor literature to know what you're looking for). You may find that most of the events are occurring on a few DFS channels that you can avoid in your deployment.
There are several excellent webinars online as well related to DFS planning. Search for DFS webinar to locate them.