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Item type:Publication, Access status: without files , Modeling challenging EMC problems(IEEE, 2017-11-02); ; ; ; A variety of numerical techniques is used in electromagnetic compatibility (EMC) for the numerical analysis of practical problems. The most important are the finite-difference timedomain technique, the finite-element method, the transmissionline-matrix method and the method of moments. All approaches have their strengths and weaknesses and cannot be applied to all kinds of problems with the same degree of efficiency, measured in memory consumption and computation time necessary. In this paper, it is shown that the method of moments (MoM) can be applied to a variety of scenarios, each of which would form a challenging problem to all of the mentioned numerical techniques. It is shown that a customization of the MoM to the specific problems at hand can be accomplished. All examples shown have been computed using the academic code CONCEPT-II developed at Hamburg University of Technology (TUHH).Publicationtype: Journal Article148 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , On the Treatment of Arbitrary Boundary Conditions Using a Fast Direct H-Matrix Solver in MoMThis communication adapts the formalism of hierarchical H) matrices to the direct solution process (LU decomposition) of the method of moments (MoM) in the frequency domain. A novel clustering approach based on physical constraints is presented and extended to treat dielectric bodies as well as arbitrary boundary conditions. Comparisons with other numerical methods are provided. The analyses show a considerable speedup of the computation times and a significant reduction of required memory compared with the traditional MoM solution process, especially for highly resonant structures where iterative solvers like the multilevel fast multipole algorithm show poor convergence.Publicationtype: Journal Article87 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Auswirkung absorbierender Materialien auf die Verkopplung von Komponenten innerhalb eines PC-GehäusesPublicationtype: Conference Paper31 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , 25 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Modeling absorbing materials in cavities with apertures using the thin sheet approximation(2015-12-17); ; ; This paper discusses the efficient treatment of absorbing materials, both dielectric and magnetic, for the calculation of electromagnetic emissions using the Method of Moments (MoM). By describing the effects of absorbing sheets with the thin sheet approximation (TSA) the number of unknowns can be reduced considerably. The validity of this approach is verified against measurements and a finite element solver (FEM).Publicationtype: Conference Paper38 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Modeling of mutual coupling between coaxial probes in flat metallic casings using the contour integral method(2015-10-12); ; ; ; This paper investigates electromagnetic interference mechanisms in flat metallic casings using the contour integral method (CIM). Coaxial monopole probes are used to represent potential radiators, and a local field model is developed and combined with the CIM for evaluation of mutual admittance between the probes. Limitations of the method are discussed.Publicationtype: Conference Paper38 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Numerical and experimental evaluation of electromagnetic coupling between radiating antenna structures inside a computer casing(IEEE, 2015-09-14); ; ; ; On the basis of a cavity structure that resembles a computer casing, this paper reports on the correlation of numerical simulations and experimental measurements of electromagnetic coupling between realistic radiating antenna structures. Several thin-wire monopole probes, attached to subminiature version A (SMA) connectors on the casing walls, are used to quantify the transmission coefficients between the antenna structures and probes up to 3 GHz. For comparison, the transmission characteristics in free space are studied by means of numerical simulations. The presented results are in qualitative agreement with results expected from theory and exhibit the influence of radiating antenna structures that go beyond canonical antenna models.Publicationtype: Conference Paper72 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , A measurement setup for quantification of electromagnetic interference in metallic casings(IEEE, 2015-07-15); ; ; ; In this paper, a test setup is proposed for quantification of electromagnetic interference (EMI) in an enclosure of digital systems. Small probes at the casing walls are used to measure the internal fields and derive network parameters for the typical coupling between internal components. It is shown that the setup is viable for estimating EMI between enclosed components in a frequency range from 10 MHz to 6 GHz. Measurement results from the proposed setup are in excellent agreement with those of analytical and numerical methods. A statistical approach is introduced to evaluate the measurement results from a twelve-port vector network analyzer at high frequencies above the first resonance. Using this approach, typical components in digital systems are analyzed and simplified geometrical models are given. These models allow full-wave simulations of realistic setups with feasible computation times. A good model-to-hardware correlation between simulation and measurement results over the whole frequency range is achieved. It is demonstrated that the proposed measurement and evaluation approach of the fabricated cavity shows the same characteristic behavior of a real office workstation with internal components.Publicationtype: Journal Article76