Microwave Office port and simulator question

[young.microwave.eng]

hi
I'm designing some circuit in microwave office and I'm going to analyze them in EM-structures too.I do the job but I have some dark parts in my mind
when assigning the ports for the layout in EM structure,there exist different ports i.e edge port and internal port.would you please tell me about them and their differences?
and the other question is about the simulators.using different simulators I have different result for my simulation.for example I simulated my design using EM sight simulator and Axiem simulator.but for Axiem simulator the result is much better.which one is more reliable?
Thanks in advance

 

[volker_muehlhaus]

there exist different ports i.e edge port and internal port.would you please tell me about them and their differences?

It's about ground reference - where does the port ground go.
John Dunn from AWR wrote some useful articles on EM ports in AWR : http://rfglobalnet.com/article.mvc/EM-Ports-A-Ground-Is-Out-There-Somewher-0001

using different simulators I have different result for my simulation.for example I simulated my design using EM sight simulator and Axiem simulator.but for Axiem simulator the result is much better.which one is more reliable?

Axiem and emsight both use MoM, just with different type of basis functions. None of them is "more reliable", it all depends on the user's experience.

If you get different answers, something is wrong with your models. My guess is that you did not set the correct cell size in emsight. Also, the settings for port de-embedding might be different.

 

[young.microwave.eng]

thanks volker for your reply
for emsight I follow the method that is described in the help of microwave office.(interdigital filter example).the settings are the same as what is said in help.the same as for Axiem.I meant the only difference is the simulator.the meshes are the same at both cases.
IS THERE ANY OTHER CONSIDERATION??

 

[volker_muehlhaus]

the meshes are the same at both cases.

Can you show a screenshot of the resulting mesh for both simulators?

 

[young.microwave.eng]

hi
thanks again for your reply
In the part that I mentioned that the meshes are the same,I meant the setting for meshing is the same.but for sure the meshing for different simulators are different too.I will upload the screen shot soon

 

[wisadsud]

thank you thank you

 

[loucy]

IS THERE ANY OTHER CONSIDERATION??

For EMSight the circuit is enclosed in a PEC boxed in the horizontal direction.
For Axiem the substate in the stackup extends to infinity along the horizontal direction.