CST simulation of a wide band antenna 3.5 - 6.5 GHz - need help

Hi all,

I'm trying to design a wide band directional antenna working in 3.5 - 6.5 GHz range (bandwidth 3 GHz) with a high gain.

I tried several types and now simulating a dipole antenna array with a reflector in CST microwave studio and got following results for return loss and realized gain

my problem is why the simulation giving above 14dB realized gain after 4 GHz, though there is a very poor return loss from 5.5 GHz - 8.5 GHz (> -4 dB)?

If I fabricate this antenna will it give such high gain like in this simulation?

Thanks,