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Undefined value- NaN or Inf found when solving linear system using SOR

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Hi, I have a patch antenna which was working on 900 MHz frequency. It was working well and giving the results. However, when i change the frequency to 10 GHz. It is showing this error-

The following feature has encountered a problem: -Feature Stationary Solver 1 (Sol1/s1) Undefined value found -Detail:NaN or Inf found when solving linear system using SOR

Please help!


2 Replies Last Post 2018年11月8日 GMT-5 23:56
Robert Koslover Certified Consultant

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Posted: 6 years ago 2018年11月8日 GMT-5 17:37

Hmm. There's more than a factor of 10x in frequency between 900 MHz and 10 GHz. (By any chance, did you actuially mean 1.0 GHz?) It would be a very unusual patch antenna to operate at both 900 MHz (aka, 0.9 GHz) and 10 GHz. Also, for such a huge change in frequency, you would probably need to remesh the problem far more finely than at the lower frequency, to obtain good numerical behavior/convergence. If you used a mesh more suitable for 900 MHz, that could be the main source of your difficulties, although one would expect bad results rather than an outright failure. Even so. Anyway, if you really meant to say 1 GHz, then maybe your problem is something much less obvious. I suggest you post your model to the forum so that others here can take a closer look at the details. Good luck.

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Scientific Applications & Research Associates (SARA) Inc.
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Hmm. There's more than a factor of 10x in frequency between 900 MHz and 10 GHz. (By any chance, did you actuially mean 1.0 GHz?) It would be a very unusual patch antenna to operate at both 900 MHz (aka, 0.9 GHz) and 10 GHz. Also, for such a huge change in frequency, you would probably need to remesh the problem far more finely than at the lower frequency, to obtain good numerical behavior/convergence. If you used a mesh more suitable for 900 MHz, that could be the main source of your difficulties, although one would expect bad results rather than an outright failure. Even so. Anyway, if you really meant to say 1 GHz, then maybe your problem is something much less obvious. I suggest you post your model to the forum so that others here can take a closer look at the details. Good luck.

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Posted: 6 years ago 2018年11月8日 GMT-5 23:56

Hi robort,

Thankyou so much for your reply. I am so sorry, I meant 1 GHz there. And yes, it was the problem with the mesh. I changed the mesh to coarse and it simulate. I have the results now but my patch antenna S11 parameter is -8.0727, can you tell me how can i make the gain near to -10?

Thankyou so much for your time.

Hi robort, Thankyou so much for your reply. I am so sorry, I meant 1 GHz there. And yes, it was the problem with the mesh. I changed the mesh to coarse and it simulate. I have the results now but my patch antenna S11 parameter is -8.0727, can you tell me how can i make the gain near to -10? Thankyou so much for your time.

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