Propagating modes with HFSS

[jander]

Hi,

I am using HFSS for studying the different modes (guided modes, radiation modes and leaky modes) in a planar structure (microstrip) and studying their behavior with frequency.

My design would be based on the following layers:

1.- microstrip line
2.- substrate
3.- air (0.5 mm)
4.- Ground plane

And my questions are:

1.- Which ports should I define? I think I should use "waveports", shouldn´t I?
2.- How should I define the ports? Should I introduce something else?

Thank you

Jander

PS: If you have graphical suggestions you could also send them to me by email: jander77@hotmail.com

 

[loucy]

I think HFSS is not the right tool for studying guided modes, not to mention the leaky mode. However, you can use it to study resonant mode of cavity.

if you are interested in only the dominant mode, then the waveport might be helpful. you can get the characteristic impedance etc. for that mode.

 

[dr_em]

I agree with loucy that HFSS is not the best tool for this task. You should try using a planar EM simulator for this, e.g. Sonnet, Momentum (Agilent), Empower (Eagleware), IE3D (Zeland), Ensemble (Ansoft), etc. Depending on how much detail you want for the mode information, Sonnet Lite may suit your needs just fine and it's free, highly accurate and easy to use. You can download it from their website: sonnetusa.com The others all cost [plenty] and might not be as simple to use, depending on your background. There was a free version of Ensemble but since Ansoft has bundled it into their Designer product, it's no longer free. If you really want it, the old free student version should be available in the download section of this board. However, you're probably better off with Sonnet as it's much more capable than the free student version of Ensemble.

 

[jander]

I have already downloaded Sonnet Lite Simulator, and as you said, dr_em, it is easy to use but I am specially interested in the leaky modes of my structure and their propagation constants and I am not sure if I could obtain this information with this Sonnet Simulator, could I?

Jander

 

[loucy]

no