Conference Agenda

Electronic based systems (EBS) tend to become smaller in size while at the same time their functionality, complexity, and the operating frequencies increase. Therefore, accurate and broadband characterization of the electric behavior of the components of such EBS is becoming more and more important for first time right designs, especially for electromagnetic compatibility (EMC) and interference (EMI) issues. Although many of the manufacturers provide the electric characterization of their components up to, e.g., 8.5 GHz, there is still a lack of information about the parasitic electromagnetic coupling of their components to others. To characterize this behavior in terms of measurement is becoming more demanding due to the small size and the high frequencies, hence the characterization by means of numerical simulations has become popular in the last years. Due to the fact that the components can be quite complex and their structure hard to model and simulate - like it is the case for the here investigated multi-layer ceramic capacitors (MLCC) - simplified models of the geometry have been typically used. Due to the specific internal structure of the MLCC, the FFT-PEEC method is a promising technique, which allows for an accurate characterization of the complete model while, at the same time, keeps the computational effort acceptable compared to, e.g., FEM. To show the capabilities of the proposed FFT-PEEC method, we present a comparison of the electromagnetic characterization of a grounded coplanar wave guide structure (GCPW) and MLCCs.

In this paper, a one-step leapfrog alternating-direction implicit finite-difference time-domain (ADI-FDTD) method is presented for simulating general lossy dispersive media. The dispersion characteristics are described by the quadratic complex rational function model with the bilinear transformation. Conformal grids are used in regions with fine structure. The obtained formulations can cover commonly used dispersive models such as Debye, Drude, modified Lorentz, and critical points. Numerical examples validate the accuracy, efficiency, and unconditionally stability of the proposed algorithm.

This article presents a finite element (FE) method (FEM) based approach for characterizing the dimension-independent magnetic and dielectric properties of Mn–Zn toroidal ferrite cores. Two 1-D axisymmetric FE models are built for solving the full-wave electromagnetic field equations in a toroidal ferrite core using either the electric field strength (E) or the magnetic field strength (H)

as the variable. It is found that the air at the center of the toroidal core has to be considered in order to obtain equivalent results from the E- and H-based formulations. Impedance measurements are performed for the toroidal cores over a frequency range of 10 kHz - 10 MHz, and the dimension-independent values of the complex permeability and complex permittivity are traced by fitting the FE model parameters so that the modeled impedances match with the measured ones.

We present a preliminary numerical evaluation of the Hybrid High-Order (HHO) method applied to the indefinite time-harmonic Maxwell problem. HHO is a recently developed member of the family of Discontinuous Sketetal methods, to which belongs also the well-established HDG method. HHO provides different valuable assets such as simple construction, support for fully-polyhedral meshes and arbitrary polynomial order, great computational efficiency, physical accuracy and straightforward support for hp-refinement.

A full-vectorial finite-difference scheme is proposed in this work to accurately extract the propagating modes on a magnetically-biased graphene microstrip. Initially, the anisotropic surface conductivity of graphene is introduced, and the appropriate eigenvalue problem is formulated starting from Maxwell equations. In particular, a finite-difference approximation is utilized, while the discretization of the computation domain is based on the popular Yee-cell. The numerical results highlight the expected difference between the propagation properties of the edge modes, thus validating the successful implementation of the featured modal solver.

In this work, it is developed an improved C-FDTD approach for Perfect Electric Conducting (PEC) materials using the Gauss-Legendre Quadrature integration technique to calculate the cell area and retain precision in coarser meshes. This work aims to to uncover new grounds onto the locally conformal approach of the FDTD method and achieve greater computational efficiency, improving the method’s performance and accuracy in poorly discretized meshes in which the original C-FDTD is less efficient. Applying the improved C-FDTD in a curved surface, the performance of the developed method is analyzed, and the resulting computational efficiency and accuracy gains are discussed.

Our goal is to demonstrate the backward wave propagation phenomenon, which is one of the properties for negative index metamaterials, by Nonconforming (NC) Discontinuous Galerkin Time-Domain (DGTD) method. With the use of explicit time integration schemes, the DGTD method performs element wise computations, thus realizing a highly parallelized algorithm. Hence, local mass and stiffness matrices in the DGTD method are not required to be assembled into a global matrix, which distinguishes the DGTD method from the finite element time-domain (FETD) method. Thus, DGTD method can perform an efficient domain decomposition, deal with unstructured meshes and avoid the inversion of a global system matrix. This paper presents the theory to modeled a metamaterial using a DGTD formulation. We report the development of a non-conforming, discontinuous Galerkin method for the solution of the system of time-domain Maxwell’s equations in heterogeneous propagation media.

Although it is necessary to investigate the optical properties of photocatalysts, it is difficult to handle both numerically and experimentally. In this study, we treat a fractal structure as a nanostructure and propose an optical model using the fractal dimension for easy estimation of optical properties. The fractal surfaces of any dimension are generated using the midpoint displacement algorithm (MDA). The optical properties are evaluated by electromagnetic wave irradiation in a fractal structure using the finite-difference time-domain (FDTD) method. The computation result shows that we were successful in following the continuous change of the optical properties. In addition, the simulation results are validated because the law of conservation of energy was satisfied. This proves the possibility of optical modeling using the fractal dimension.

The authors have investigated a high-accuracy the electromagnetic field analysis for voxel models based on a parallel finite element

method with a mesh smoothing algorithm. The numerical human body models based on the voxel mesh generated from computed

tomography images are represented, and composed of skin layers, blood vessels, bones, internal organs, etc. In this paper, we propose a

mesh smoothing technique to reduce the noise caused by the reflection and scattering of the electric fields around material boundaries. The

mesh smoothing has been verified by TEAM Workshop #29 that is a benchmark problem for the full-wave electromagnetic field analysis.

In this study, the finite-difference time-domain (FDTD) method is employed to simulate electromagnetic wave propagation in several types of fuzz structures generated in tungsten. Moreover, the midpoint displacement algorithm (MDA) is adopted to describe typical structures of fuzz in tungsten fractally, and the fractal dimension size of fuzz structures can be controlled by the method. To analyze electromagnetic penetrations and reflections of the fuzz structures, we use the three-dimensional empirical mode decomposition (TEMD) to decompose simulation results in the spatial frequency domain. The results of computation show that electric field intensity distribution is decomposed into residual intrinsic mode functions (IMFs) and one residual, which indicate resonances caused by hitting the surface of fuzz structures from high spatial frequency to low spatial frequency. As a result, IMF has the highest spatial frequency represents the penetrations and reflections caused by fuzz structures. On the contrary, IMFs with lower spatial frequency represent the ranges of penetrations and reflections, canceling electric field intensity exceed in IMF1 to keep the superposition property. These decomposed IMFs reveal the relationship between fractal dimension sizes and their optical characteristics in the fuzz structures.

We discuss an implementation on recent GPU hardware of the Time Domain Discontinuous Galerkin method for the Maxwell equations. We assess the performance of the method on the simulation of an electrostatic discharge test.