HFSS! How to explain some ripples in S parameter curves

[parris]

Dear all

I got confused about this problem for a long time when using HFSS.
Do you meet this phenomenon in your work?

How can we avoid this problem and let the curves be smooth when doing the simulation?



Looking forward to your advice and explanation

 

[wandering heart]

Maybe this is not the problem of HFSS, in CST they exist as well.

Is there any physical origin?

 

[f6dro]

Hello ,

true , I often, get this pb as well. It looks like the structure ( mesh?) is resonnating.
I've tried to refine the mesh , but the pb was still there , so I have no idea on how to solve this. I have been told the V11 HFSS version solves this?

Dom

 

[parris]

Dear wandering heart and f6dro

Thanks for your responses. I put forward this problem with the hope for a hot discussion.I have tried and this phenomenon still happens in HFSS11.

Cheers
Parris

 

[VSWR]

Could be many reasons. WinRAR your HFSS project files and post here.

 

[parris]

Dear all

At last I just changed the structure and remove the ripples out of the required bandwidth.

Thanks for your attention!

Regards
Parris

 

[ptshao]

Hello, everybody:
I remember if there is impedance mismatching at port, then ripples appear on s plots. It might be a common thing.

Welcome comments from others!

 

[shahid78]

hi everyone

you will get ripples in S parameters whenever your simulation finishes before the energy in the computational domain decays sufficiently?

so increase the accuracy to around -50db or -60db for enerygy to decay sufficiently at the time ur simulation finishes. this will remove the ripples in S parameters

i hope this answer ur question

cheerzz