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Purpose: The purpose of this study is to introduce a novel method for the measurement of electromagnetic material parameters. Design/methodology/approach: The main idea behind the approach is the fact that for slabs with elongated shapes, the intensity of the backscattered field and the electromagnetic resonance frequency corresponding to the length of the sample are dependent on the conductivity of the sample's material. Findings: It is shown that for a known scattered field and resonance frequency, it is possible to formulate an inverse problem as to the calculation of the conductivity of the sample's material at the considered frequencies. To investigate the applicability of the method, demonstrative experiments are performed during which the micro-Doppler effect is used to increase the measurement accuracy. The idea is extended to the case of anisotropic samples, with slight modifications proposed to the experimental setup in the case of significant anisotropy in the investigated material. Practical implications: The measurement method may prove useful for the investigation of the high-frequency conductive properties of certain materials of interest. Originality/value: To the best of the authors' knowledge, this is the first time the use of the micro-Doppler effect is proposed for the purpose of the measurement of material parameters. [ABSTRACT FROM AUTHOR]

Purpose The electromagnetic modeling of inductively coupled, resonant wireless power transfer (WPT) is dealt with. This paper aims to present a numerically efficient simulation method.Design/methodology/approach Recently, integral equation formulations have been proposed, using piecewise constant basis functions for the series expansion of the current along the coil wire. In the present work, this scheme is improved by introducing global basis functions.Findings The use of global basis functions provides a stronger numerical stability and a better control over the convergence of the simulation; moreover, the associated computational cost is lower than for the previous schemes. These advantages are demonstrated in numerical examples, with special attention to the achievable efficiency of the power transfer.Practical implications The method can be efficiently used, e.g., in the optimal design of resonant WPT systems.Originality/value The presented computation scheme is original in the sense that global series expansion has not been previously applied to the numerical simulation of resonant WPT. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to propose an efficient numerical simulation tool based on FEM, by which the EMC shielding effect characteristics of power cables can be predicted in the 30-1,000 MHz frequency range, as if it would be measured by the absorbing clamp method. Design/methodology/approach – The simulation method is based on decomposition: a 2D axisymmetric RF FE model is used for describing the whole measurement set-up, while a 3D quasi-static FE model is used for the symmetry cell of the shielding layer in order to capture the effect of its fine geometric details. Findings – Comparison with real measurements shows that the shielding characteristics can be reliably predicted this way, with some deviation in the low end of the frequency range though. Practical implications – This simulation tool can be applied in the design and optimization of braided cable shields to be used in the automotive industry. Originality/value – Two numerical models are coupled by the novel concept of "equivalent shielding layer", which is obtained by homogenization. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to accelerate the time-consuming task of assembling the impedance matrix resulting from the discretization of integral equations by the moment method, accelerated using massively parallel processing scheme. Design/methodology/approach – This paper provides several approaches for the implementation of moment method on compute unified device architecture (CUDA) capable general purpose video cards, as well as giving general implementation design patterns and a good overview on the topic. Findings – The proposed method seems to be efficient in the light of the presented numerical results. Originality/value – The subject of the paper is an evolving, considerably new aspect among computation techniques which could be of high interest for the scientific community. [ABSTRACT FROM AUTHOR]