Request: Microstrip Array Gain = 40 dB... is it possible?

Hello RF people,

this morning I was just wondering if it's possible to design a microstrip antenna with Gain more than 40 dB in RHCP.

I mean a "complete" antenna.. including BFN losses..

Let's say that the pattern is fixed..

My feeling is that it is not achievable... I'm open to discuss with array experts..

What do you think?

Regards

Lupin