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3D optical waveguide error

Hello everyone,

What I'm trying to do is basically simulate an optical fiber in 3D. I thought it would be a simple task but I'm running into an error.

I created an optical fibre with an air cladding. The fiber is very thin (.5 um radius).

I thought all I would have to do was create an input port and and exit port, perform a boundary mode analysis on both ports and then add the frequency domain study.
When I do this i get the following error:

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

Does anyone know what I am doing wrong? Any input would be greatly appreciated.

Thank you,
Mark

6 Replies Last Post Jul 9, 2013, 3:32 AM EDT
Abutaleb Haidary
Posted: 4 years ago Jun 10, 2013, 12:47 PM EDT
Hi,
Which kind of excitation port you are using for this 3D model?
Hi, Which kind of excitation port you are using for this 3D model?

Posted: 4 years ago Jun 11, 2013, 1:43 AM EDT
I'm using a numeric port. Should I try a user defined port?
I'm using a numeric port. Should I try a user defined port?

Posted: 4 years ago Jun 18, 2013, 12:30 AM EDT
Is there any way to solve for a field in a 2D model and then import that solution into the 3D model for the boundary mode analysis and then see how it propagates in the 3D model?
Is there any way to solve for a field in a 2D model and then import that solution into the 3D model for the boundary mode analysis and then see how it propagates in the 3D model?

Posted: 4 years ago Jun 19, 2013, 5:28 AM EDT
One last question. I hope someone will answer :)

In the 2D model of a circular optical fiber you can see the modes present. If I make a 3D fiber and only perform a single boundary mode analysis on one input should I be able re recreate the 2D models results? I've tried this with no luck thus far.

Thanks,
Mark
One last question. I hope someone will answer :) In the 2D model of a circular optical fiber you can see the modes present. If I make a 3D fiber and only perform a single boundary mode analysis on one input should I be able re recreate the 2D models results? I've tried this with no luck thus far. Thanks, Mark

Posted: 4 years ago Jul 9, 2013, 12:52 AM EDT
Hello again,

I've updated to 4.3b and I'm trying a similar model. I think what I have should work but I can't get it to compile.

Could someone take a look at my model and see if there are any obvious mistakes? The solver gets to about 70% but then it stalls for a long time. I think my mesh is correct.

Any advice is welcome!

Mark.
Hello again, I've updated to 4.3b and I'm trying a similar model. I think what I have should work but I can't get it to compile. Could someone take a look at my model and see if there are any obvious mistakes? The solver gets to about 70% but then it stalls for a long time. I think my mesh is correct. Any advice is welcome! Mark.


Posted: 4 years ago Jul 9, 2013, 3:32 AM EDT
Here is my two cents.
Don't have the RF module so I can't take a look at your model but if the solver stalls, it means there are convergence issues; as the model is quite simple (or it should be) this means something is wrong with the physics.

Here is my two cents. Don't have the RF module so I can't take a look at your model but if the solver stalls, it means there are convergence issues; as the model is quite simple (or it should be) this means something is wrong with the physics.

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