How to see input impedance at edge of patch antenna using Sonnet?

[Terminator3]

Hello!
I tried doing the following:
put autognd port on patch edge, run simulation, chose Zin graph.
Problem is that Zin is around 50 Ohm at my frequency, wich differs from emtalks calculator that gives value of 200 Ohm ( https://www.emtalk.com/mpacalc.php )

As i understand, Zin is right what i need, but so huge difference makes me doubt this.

 

[fiwi]

Hello!
I tried doing the following:
put autognd port on patch edge, run simulation, chose Zin graph.
Problem is that Zin is around 50 Ohm at my frequency, wich differs from emtalks calculator that gives value of 200 Ohm ( https://www.emtalk.com/mpacalc.php )

As i understand, Zin is right what i need, but so huge difference makes me doubt this.

,,,see the Dielectric Constant (εr)....!!!

 

[BigBoss]

Autognd ports are used as internal ports, they need calibration plane.
You should use standard ports.

 

[volker@muehlhaus]

Autognd ports are used as internal ports, they need calibration plane.
You should use standard ports.

No, both port types are fine. The autognd will create the ground access in vertical direction (via) and the standard box wall port will create it in horizotal direction.

Of course, for the autogrounded port, we would need to set the proper port width. We don't want the port to extend over the entire edge. Otherwise, we would simulate an open ended line stub. So practically, to control the correct feed, it is easier to add some length of feedline.

I am not really sure what the "input impedance at the radiation edge" means for this online calculator. Is this some theoretical value over the entire edge, or is this the input impedance when connecting a 50 Ohm line (with reference location at the edge)?