Re: inverted-PIFA simulation result from book different from
By the look of your layout you have attached three ports to your structures. This enables you to excite the two modes of your CPW, the quasi-TEM mode and the slot mode. Now the mode which you probably mean to be excited in your prototype is the quasi-TEM mode. In other words, your prototype will include an element such a bridge which will short the slot mode and prevent it from propagating into the rest of your system, radio or what have you...
This is where your simulation layout may differ from your prototype. Indeed, depending on how you excite / load the ports in your simulation file, the slot mode might be excited in a way which does not correspond to reality.