Frequency Analysis of Rounded Shaped Inductive Metallic Objects in Waveguides via some PEC Approximations and GSM Method

Abstract

A hybrid method is proposed for the frequency analysis of rounded metallic objects inductively loaded in rectangular waveguides. The proposed method combines the efficiency of the generalized scattering matrix method (GSM) and the flexibility of the method of moments (MoM) and the fact that fields cannot exist inside perfect electric conductors. Metallic discontinuities are modelled as a dielectric medium with extreme conductivity and the volume is emptied except the surrounding area. The proposed method is tested against several structures including a band-pass filter composed of metallic rods and an arbitrarily shaped discontinuity. The accuracy of the method is compared to commercial software based on the finite element method. The proposed method is exclusively competent for the frequency analysis of rounded or arbitrarily shaped metallic discontinuities.

Keywords

• Arbitrarily shaped discontinuities
• computational efficiency
• microwave devices
• waveguide discontinuities.
• generalized scattering matrix method

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