Surface impedance of an EBG

Hello

I have to evaluate the Surface Impedance of an EBG structure in CST (I'm using CST 2012).
How can I do?

Tranks

I think you want to fine dispersion diagram for evaluating the performance of an EBG structure in CST, this ex can be useful to do this.
http://iribu.ac.ir/sitepics/gallery/...QuickGuide.pdf