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Boundary conditions for Eigenfrequency analysis
Posted Feb 18, 2014, 11:15 a.m. EST RF & Microwave Engineering Version 4.3 0 Replies
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Hi all,
I would be greatful if someone here could help me.
I am trying to simulate the resonance of a simple metallic dipole antenna
With a small gap in the middle for field concentration at THz freqs.
I am performing an eigenfrequency analysis with an initial guess at
2x the antenna length for the wavelength.
I am trying scattering boundary conditions applied to the outermost boundary of the air volume that surrounds the antenna.
For the Eigenfreq analysis I am inputting a linearization point of -i*2*pi*freq,
Where freq is the guess freq (as above).
The problem is as follows:
The eigenfrequency for the resonance I am interested in (dipole with
Field concentration in the middle) shifts in frequency depending on the
Extent of the air voulume in which I place it.
I have plotted the freq vs the air volume size (lets say it is a sphere but it also changes for other shapes) and there seems to be no saturation, aka I get a linear fit.
I would be greatful if someone could help me see what I am doing wrong in my analysis as I am unfamiliar with eigenfrequency analysis.
Regards,
David J
Hello David Jessop
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