Laboratory reply as below:
Usually DFS doesn’t need to re-test if the new antenna gain is bigger than the original,
but you will modify the threshold setting of EUT after the new gain declared,
threshold value will affect the radar detection rate, so I suggest to do the verification test.
We will do CAC & In-service monitoring test for both bands/ one worst bandwidth.
If verification test is pass & radar detection ability doesn’t decrease, the original test data can be used for new antenna gain.
On the other hand, if the test fails or detection ability is much worse than the original test result, we must re-test the DFS.