great difference between the simulation results of HFSS&

Hello,everyone.

I want to design a W-band E-plane waveguide bandpass filter, I adopt HFSS and CST to analyze the filter with the same structure parameter, but the results show great difference, they are totally different.

The attachment is the projects of HFSS and CST.

Can anyone give me some advice?

Thank you!

I believe you HFSS design differs from the CST MWS.

Somethings I noticed.
1.You have no boundaries for HFSS
2.Wave port excitation into vacuum with no conducting boundaries in HFSS
3.You are essential exciting a mode into a vacuum waveguide? Can it maintain this mode?

tekz, thank you for your replying.

1. according to the help document of HFSS, its background will be set to be PEC automatically. So since it's a waveguide, I think I can let the boundary empty.

2. I remenber that if the waveport was defined totally in the boundary, then a conducting boundaries should be defined to shield it……

If you have some useful materials, would you please share them with me?

@ sonofsky:
how did u convert the HFSS file for opening in CST format?

Hi can you explain me how I can import,convert HFSS project to CSTs

They look pretty similar to me.

hello all
in hfss file solution frequency is 94GHz but in frequency setup it selected between 1 and 10 GHz(!)