Assessment of shielding effectiveness by using electromagnetic topology method

Download
2013
Yaşlak, Halil İbrahim
In this thesis, determination of the shielding effectiveness of a rectangular shielding box with apertures on its walls by using electromagnetic topology (EMT) technique based on Baum-Liu-Tesche (BLT) equation is presented. The presented technique is applied to determine the field penetration into various rectangular shielding boxes with different sizes and aperture dimensions. An HP branded computer case is also analysed as a rectangular shielding box with a CD driver slot as an aperture. Results on electromagnetic field penetration through the apertures into the boxes at different frequencies are obtained by using the presented method and compared with the results obtained by using CST MICROWAVE STUDIO® software simulation.

Suggestions

Hybrid CFIE-EFIE solution of composite geometries with coexisting open and closed surfaces
Ergül, Özgür Salih (2005-07-08)
The combined-field integral equation (CFIE) is employed to formulate the electromagnetic scattering and radiation problems of composite geometries with coexisting open and closed conducting surfaces. Conventional formulations of these problems with the electric-field integral equation (EFIE) lead to inefficient solutions due to the ill-conditioning of the matrix equations and the internal-resonance problems. The hybrid CFIE-EFIE technique introduced in this paper, based on the application of the CRE on the ...
On the Accuracy and Efficiency of Surface Formulations in Fast Analysis of Plasmonic Structures via MLFMA
Karaosmanoglu, B.; Yılmaz, Ayşen; Ergül, Özgür Salih (2016-08-11)
We consider the accuracy and efficiency of surface integral equations, when they are used to formulate electromagnetic problems involving plasmonic objects at optical frequencies. Investigations on the iterative solutions of scattering problems with the multilevel fast multipole algorithm show that the conventional formulations, especially the state-of-the-art integral equations, can significantly be inaccurate, in contrast to their performances for ordinary dielectrics. The varying performances of the form...
Accurate analysis of metamaterials involving finite arrays of split-ring resonators and thin wires
Gurel, Levent; Ergül, Özgür Salih; Unal, Alper (2007-03-30)
In order to gain physical insight into how some metamaterial structures behave, we report our results obtained by accurate numerical solutions of electromagnetic problems related to various constructions of split-ring-resonators (SRRs) and thin wires (TWs). Single and multiple layers of arrays of SRRs and TWs are investigated in detail using the electric-field integral equation. Without utilizing any homogenization techniques, we accurately model large numbers of unit cells that translate into very large co...
Accuracy of the Surface Integral-equation Formulations for Large Negative Permittivity Values
Karaosmanoglu, B.; Ergül, Özgür Salih (2017-05-25)
Computational solutions of plasmonic problems involving metals at optical frequencies formulated with surface integral equations are considered. Numerical inaccuracies arise when using the conventional formulations for penetrable bodies, especially as the negative real permittivity becomes very large at the lower frequencies of the optical spectrum. In order to close the gap between plasmonic and perfectly conducting simulations, it is required to extend the applicability of surface integral equations to in...
Multi-frequency contactless electrical impedance imaging using realistic head models : single coil simulations
Gürsoy, Doğa; Ertan, Hulusi Bülent; Department of Electrical and Electronics Engineering (2007)
Contactless electrical impedance imaging technique is based upon the measurement of secondary electromagnetic fields caused by induced currents inside the body. In this study, a circular single-coil is used as a transmitter and a receiver. The purpose of this study is twofold: (1) to solve the induced current density distribution inside the realistic head model resulting from a sinusoidal excitation, (2) to calculate the impedance change of the same coil from the induced current distribution inside the head...
Citation Formats
H. İ. Yaşlak, “Assessment of shielding effectiveness by using electromagnetic topology method,” M.S. - Master of Science, Middle East Technical University, 2013.