CST： strip line between

CST
Hello everyone, I have doubts about '' g '' second link below. I did not find material on the subject. Where there are two openings in the antenna power line. (between the power line has spacing)

Hi,
I believe the parameter "g" is to get better antenna matching impedance. You can try to simulate the dimension of the parameter "g" & "d" by using CST.

To get the best compromise (impedance matching and radiated power), g should be about 1.5 x Wf.

Google for "inset tuned patch antenna"

Thanks, but can anyone indicate the book or material might better help develop this? I did not find good about it.