Learning Forum

[Jagmohan]

I have designed a coplanar waveguide that should resonate around 3 GHz. I get different resonant peaks of S21 while giving a different solution setup(i.e. Different solution frequency ). In the HFSS manual, the explanation is given that the results are not affected while using the discrete solution setup. But I am getting different S21 at different frequencies when the solution frequency is changed.

Please help me!

Thank you,

Jagmohan

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[AndyJP]

1) Theres something weird because it is not just a shift but a change in the character.
2) Strictly speaking, FEM gives correct results only at meshing frequency. The closest frequencies may reuse the mesh, particularly in lower band, if there are no peculiarities, like cutoffs and resonances. in that way solve bands separately, or in new HFSS versions set multiple frequencies above and below the peculiarities.
3) Use discrete sweep, check that there is no mistake and it is really discrete.
4) Set number of passes to 15-20, and the convergence to 0.05. The default is only good for simple straight lines.
Try 2nd order or mixed order solver.

[Praneeth]

Please use upload image option of the forum instead of as attachments as Ansys employees will not be able to access them.
Kindly provide more details of the solution setup and the results.
Best regards