Reflection coefficient graph yielding non physical results when I add a far field request

Ianrchavez
Ianrchavez New Altair Community Member
edited October 2020 in Community Q&A

I'm having a weird issue, and I'm hoping there's a simple solution here.

I made a patch antenna with a rectangular cut out. 

When I simulate it without requesting a far field, it gives me results that seem physical. 

As soon as I add the far field request, my reflection coefficient plot yielded non physical results. 

Nothing changed about the model, I simply requested a far field. 

 

 

 

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Answers

  • Mel
    Mel Altair Community Member
    edited July 2020

    Please attach the *.cfx

    The *.cfs is the session file :-)

  • Ianrchavez
    Ianrchavez New Altair Community Member
    edited July 2020

     

    I can not attach the model. 

  • Ianrchavez
    Ianrchavez New Altair Community Member
    edited July 2020

    I just changed the solution frequency range, and I'm getting better looking results, but I still do not understand why the reflection coefficient graph would change at all. 

  • Mel
    Mel Altair Community Member
    edited July 2020

    The Green's Function for infinite substrates uses interpolation tables. Over frequency ranges the algorithm used is changed at some point over the range. A small glitch could be observed at a specific but narrow frequency range. Adaptive frequency sampling will 'zoom in' on this glitch and appear to amplify the glitch.

    If you rerun with linearly spaced discrete points the results should be the same with or without the far field.

     

    I see that you are not a University user. If you are a commercial user please contact your local Hyperworks representative for further support.