False DFS detection on firmware 4.5.0

in the setting phase of numerous radio bridges (about 15) installed in the same city, we are detecting a large number of antennas that stop propagating the signal indefinitely with the motivation in question "No Transmit due to DFS", this issue by setting different channels (tried practically all the available frequencies), both automatically setting the search for the optimal channel AFS (we are using 20 Mhz channels to reduce the amount of interference). The same behavior also occurs on the slave antennas that suddenly identify a phantom Radar and turn off the radio part interrupting the link.
The antennas are of the following types:
epmp2000 both with sectorial antenna and with integrated antenna
Force 180 (epmp1000) with integrated antenna
Force 300-25
with firmware 4.5.0

The phenomenon, which is so evident and above all on all DFS frequencies, leads us to think that the antennas are detecting normal radio interference such as radar and therefore make it impossible to establish durable links.

Could you give us support in order to solve this serious problem?
Is it possible to use non-DFS channels especially on short links (some 100 - 200 m)? In fact, non-DFS frequencies are not listed in the list available on the master antenna (in TDD mode, epmp Master, TDD PTP, etc.).
Is it possible to turn off or limit the intervention of the DFS (maybe via cli)?
Possibly there is the possibility to downgrade the firmware from 4.5.0 to 3.5.6 which on the forums is identified as a more stable version and affected by minor problems related to False DFS detection?

Thank you in advance.

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If in your regulatory region use of non-dfs channels is allowed there is no reason not to use them.

Make sure you aren't exceeding allowable EIRP by entering correct antenna gain into the AP.  Also make sure there aren't any RF-reflective surfaces in close proximity to any of the units, as the reflected energy can cause DFS hits.  Sometimes on-channel or adjacent channel noise will also cause the DFS hits.  On other occasions, the DFS detection algorithm is simply wrong.  This can be frustrating.


I can't select other channels than DFS (in select box there aren't noDFS channel),

I can select only from 5480 to 5715 , at least on short distance bridges I would like to select non-DFS channels but I can't .. 

To remain in the EIRP limit (30 in Italy) I set for example 18 Antenna Gain and 12 Transmit power on epmp2000 with Sector Antenna, for Force 300-25  25 for antenna gain and 5 for Transmit power.


my problem is the same. i have epmp3000 + force 300, fw 4.5.0 and when a start speedtest then force 300 saw radar detect and thats all. client is disconnect from epmp 3000.

this is horrible. 

is firmware 3.5.6 more stable in dfs detection?

We did improvements in context of false radar detection in 4.5.4 FW( after RC7).

Please try 4.5.4-RC16 which will be released as Beta#2 on Monday.

Thank you.