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The Problem: the maximum gain is bigger than the maximum directivity.

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Hi,

In the attached file which is a microstrip antenna model, the value of maxGaindB is bigger than that of maxDdB. I couldn't find the reason. Do you have any idea?

Thanks.



2 Replies Last Post Sep 17, 2020, 1:27 p.m. EDT
Robert Koslover Certified Consultant

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Posted: 4 years ago Sep 17, 2020, 12:38 p.m. EDT
  1. Well, it's not much bigger, is it? And the materials in your design have no losses.
  2. I also suggest you compare the realized gain to the directivity.
  3. Consider also using a finer mesh.
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Scientific Applications & Research Associates (SARA) Inc.
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1. Well, it's *not much* bigger, is it? And the materials in your design have no losses. 2. I also suggest you compare the *realized* gain to the directivity. 3. Consider also using a finer mesh.

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Posted: 4 years ago Sep 17, 2020, 1:27 p.m. EDT

Hi Robert,

  1. Well, it's not much bigger, is it? And the materials in your design have no losses.

Should I accept this situation as they are almost same but the small calculation errors causes this result. If so, I won't worry about it.

  1. I also suggest you compare the realized gain to the directivity.

I had done it. Realized gain = 7.3393, directivity = 7.3388. The gain is winner again :).

  1. Consider also using a finer mesh.

The results obtained with extremelly fine meshes: Maximum directivity, dB: 7.3388 Maximum gain, dB: 7.4306 Maximum realized gain, dB: 7.3393.

Thank you.

Hi Robert, >1. Well, it's *not much* bigger, is it? And the materials in your design have no losses. Should I accept this situation as they are almost same but the small calculation errors causes this result. If so, I won't worry about it. >2. I also suggest you compare the *realized* gain to the directivity. I had done it. Realized gain = 7.3393, directivity = 7.3388. The gain is winner again :). >3. Consider also using a finer mesh. The results obtained with extremelly fine meshes: Maximum directivity, dB: 7.3388 Maximum gain, dB: 7.4306 Maximum realized gain, dB: 7.3393. Thank you.

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