radome hfss

Hi!

I have to simulate the behavior of an antenna (a simple dipole) surrounded by a radome.

My professor told me to plot the gain at different thickness of the radome.

I have notice that if I plot the rE (db) (the power of the E field) I obtain the maximum value with the antenna with no radome, and it decreases as the thickness of the radome increase.

But if I plot the gain the behaviour is not the same.
Shouldn't I obtain a similar behaviour, obvioulsy with different values?

Because the gain, from definition, is normalized by the gain of an isotropic antenna and that shoul be fixed, isn't it?

Thanks for your help.

Don't you notice the gain changing when the thickness gets to a half wavelength.

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