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Relation Eigenvalue/Eigenfrequency problem
Posted Oct 4, 2012, 8:07 AM EDT RF & Microwave Engineering, Studies & Solvers Version 4.2 1 Reply
1) How are the eigenvalue and the eigenfrequency studies related to each other?
Typically, in two dimensions the three dimensional EM equations without any sources boil down to
(∇² + ε_r(x,y) k²) E(x,y) = 0
such that one would assume that the eigenvalue λ should be related to the eigenfrequency k simply by λ = k². However, when I simply switch from an eigenvalue study to an eigenfrequency study. I get completely different solutions. The solutions from the eigenfrequency study are not found in the eigenvalue study and vice versa.
2) Comparing the eigenfrequencies from the calculations for a simple circular dielectric cavity to the actual analytic results (which can easily be obtained for such a system), the calculated eigenfrequencies don't match, although convergence regarding the mesh discretization has been reached. Although the real parts of the eigenfrequencies roughly match, the imaginary parts are off by 5 orders of magnitude.
I would be happy for any suggestions!
Hello Tommy Cevi
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