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Propagation in PEC waveguide
Posted 28.08.2011, 12:30 GMT-4 RF & Microwave Engineering, Modeling Tools & Definitions, Parameters, Variables, & Functions, Studies & Solvers Version 4.2 1 Reply
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I was trying to simulate a rectangular waveguide (side=500nm) with PEC sidewalls. I am using a port boundary condition to excite a TE01 wave from the top and use another port condition at the bottom of the waveguide. I find that the wave cut-off is exactly at 1000nm as it should be, and for wavelengths higher than 1000nm the wave is getting attenuated. However, for wavelengths below the cut-off I am getting and error as:
Attempt to evaluate real square root of negative number.
- Function: sqrt
Failed to evaluate variable.
- Variable: mod1.emw1.alphaport_2
- Defined as: sqrt((((1428571.428571428638*pi)^2)+(-(mod1.emw1.k^2))))
Failed to evaluate expression.
- Expression: imag(mod1.emw1.alphaport_2)
I am unable to figure out this as I expect waves to propagate below cut-off wavelength as well.
Any comments/suggestions would be greatly appreciated. I am attaching my model file with the post.
Thanks,
Naresh
Attachments:
Hello Naresh
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I know you had posted a few years back, however, were you able to find a solution for this error? I am running into it and have no idea what it means.
Thank you,
Alfredo