I am designing circular disc monopole antenna but i can not get the desired response so i want to optimize the patch but i can don't know how i optimize the circular patch . i want increase and reduce the radius of circular patch by optimization .
I don’t know about first or second edition of Balanis book, but 3rd edition in chapter 14 have a lot of explanations how to design and optimize a circular patch antenna.
I think Balanis solves for broadside radiation (like rectangular patches). You see very few articles for circular patches with omnidirectional radiation.