Problems with DFS

We need to provide internet access service to an airfield and therefore we are having a lot of problems with the DFS frequencies.
We have a Force300-25 installed. Would it be possible to do some configuration so as not to have to use DFS?

Yeah… don’t use DFS channels! Use 5.1-5.2 or 5.7-5.8.

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Thanks for your answer.
I have tried but according to the Master configuration it only allows me to use the DFS frequencies 5,490-5,580 and 5,670-5,705. Do I have to change any other configuration in the Master?

This is the current configuration

Where are you located? I’m not familiar with what bands are allowed under the region “Generic ETSI”. It may be that the region “Generic ETSI” has a very limited set of 5GHz bands.

our location is spain.

I do not know if it is possible to change that parameter

Looks like if you’re in Europe… then you don’t have access to 5.1-5.2 outdoors (only indoors), and no access whatsoever to 5.7-5.8. That only leaves DFS channels for you to use.

Right, we are in Europe.

The fact is that the link is disconnected very often due to problems in the DFS frequencies.

And even if you configure alternative frequencies, you would suffer cuts while connecting to the next frequency.

Would it be possible to use other equipment?

Switch country to other via support page and problem will be resolved :slight_smile:

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It would also be illegal, and not something Cambium would condone.

Spain has special 5Ghz channels that are not ETSI specific, have you applied the country specific license to the radios?
Have you considered 2.4Ghz? ETSI restrictions does not have DFS in 2.4Ghz the last time I was digging through them about a year ago.

DFS can be mitigated by having the AP on the end that has its back to the DFS source (assuming since its an air field that it has weather radar) also running a spectrum scan with a e3000L on a similar sized & gain dish will give you an idea of which DFS channels to avoid. There is also the consideration of using smaller channel widths so your link isnt as sensitive to DFS actions as your not taking up as large of RF bandwidth. If you need the throughput then with GPS timing and dual links you can use LACP to get the throughput needed with the advantage that DFS will not usually affect both links on widely separate channels at the same time.
Just some thoughts of how we deal with this type of issue.


Removing the region code and using the permitted frequencies will not be against the law. However, it will allow you to bypass the problems with DFS, which can sometimes make life terribly difficult :slight_smile:

Have you looked at PTP550?

Would it be possible to use other equipment?

What is the distance of the link and how much bandwidth are you needing ? As some have pointed out 2.4Ghz might be an option for you though normally that spectrum is completely trashed in non-rural areas (5Ghz only slightly better). Not sure what frequencies are available in Spain but depending on that and distance of the link and rainfall 60Ghz and 24Ghz might be an option. Also, depending on your regulations 3Ghz could be a great solution. In the US there is also licensed frequencies like 11Ghz that would probably work very well about anywhere 5Ghz would work. Also, depending on the amount of bandwidth you need 900Mhz might be an option for you.

I’m not familiar with regulations outside FCC land. Are all the channels considered “DFS” a world wide thing or do Cambium radios just consider DFS channels to be DFS channels regardless of what country they are used in ?

Good morning, thank you all. I have already been able to resolve the problem momentarily, by activating the Force300 license in other.

Changing the region code is itself a violation of the regulations which these radios were qualified under. Each region and country has its own regulations that must be adhered to or the consequences could be quite alarming. Dont play routlette with your company, call your regulations office and ask what you can do, they will help you with some of the best, if not the cheapest, methids to stay compliant!

Gracias por tu respuesta, al final desinstalamos el punto a punto.

Un saludo