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Desperately Need HFSS Help: no far or near field data

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costox

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Hi all,

After I finished simulating a planar array, I CAN plot S11 but I CANNOT plot the fields:

After create-report for the near or far field, the plot shows that the field (or the gain, or Etotal, or anything else) is "nan", which I think means infinitely small number or something ?.

This despite I've added the Near and Farfield setup. I've tried all possible combination: waveport vs lumport, sheet vs object. Same problem occurs.

I've been using HFSS for more than 2 years but I still cannot figure out this problem for the last 6 months.

Thank you for shedding some light into this. I appreciate your help very much.

xox
 

ghb

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insure that the area that you setup for radiation is defined on all faces as a radiation boundary, not impedance or anything else.
 

costox

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Yes,

The rad boundary box has been correctly drawn and setup as rad boundary.

Report of S11 is ok means, I think, all the setup is ok.

Only the far fields data are missing (I've setup a sphere).
 

blessedme

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hi costox,
Verify also that the 'solve port only' is not selected from the Solution Set Up Menu.
Some other cause might be the radiation impedance being purely imaginary or with a too small real part for the fields to radiate away. I simulated a DRA today and the S11 looked good but the Z_in was imaginary at the picks of S11 below -10dB and i got no radiation fields.
 

costox

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Blessedme,
Yes, "solve port only" was UN-CHECK.
You might be right about the "rad resistance" too small.
Please tell me if you see only "nan" instead of a number (value) in the report (data table), for Etotal and whatever you choose (except S11).

If you get all the "nan", then we have the same problem.

How do we increase the radiated field ?

xox
 

nchamber

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make sure that you insert a far-field set up (right click the radiation icon) after the solution has converged.

in the project manager window:

1. select "Insert far-field setup"
2. select "Infinite sphere"
3. right click results icon - there should be an item in the menu "create far-fields report"

Bob's yer uncle.
 

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