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A high resolution interpolation scheme for use with the FDTD method at ELF frequencies under water is described. Since the interpolation is applied after the FDTD Simulation, it adds very little to the computation time or resources.
In this paper, we propose a high-speed FDTD algorithm for GPU. Our algorithm includes two important techniques: coalesced global memory access on a GPU board and the improved cache block algorithm for GPU which resembles that for the central processing unit (CPU). Our algorithm achieved an approximately 20- fold improvement in computational speed compared with a conventional CPU at the maximum computational...
The analysis of periodic structures is of great interest for engineers and scientists in a variety of applications. EMC design, antenna design, photonics, and LO design are examples of such areas. In previous works, it has been shown by these authors and others that such analyses may be accurately accomplished in the frequency or time domain. While previous works have been successful for a variety...
The family of PML boundary conditions remains important not only to standard FDTD but also to new and emerging parallel implicit FDTD methods. We have applied CPML for the first time to parallel ADI-FDTD code, finding that it is preferable to slightly increase the computational load at the saving of communication overhead, by calculating PML buffer data locally in each sub- domain that requires it,...
This paper addresses the integration issue of a multi-sector antenna on a wireless camera from simulation and application point of view. First the multi-sector antenna system is presented. Then simulation results of the full structure (antenna + camera) using both Ansoft's HFSS software and a dual-grid FDTD (DG- FDTD) multi-resolution method are presented. The obtained results are finally compared...
This paper presents an efficient, 3-D alternating-direction-implicit finite-difference time-domain (ADI-FDTD) method for modeling wave propagation in Debye dispersive media. The efficient algorithm features a simpler, matrix-operator-free right hand side than the conventional ADI-FDTD method which results in substantial reduction of floating point operations (flops) counts and memory indexing. Formulation...
The use of Graphical Processing Units (GPUs) to perform computational electromagnetic simulations has been proven over past several years to increase the calculation speed. By examining the various mathematical processes used in various techniques, appropriate algorithms for the GPU can be developed to speed up the simulations. Understanding how to map algorithms appropriately to the GPU is of vital...
In this paper the limitations of the cloak's transient response were studied. It can be concluded that the ideal cylindrical cloak, even though it is supposed to be ldquoidealrdquo, has some drawbacks. The highly dispersive nature of the device is the main reason for these limitations, which are directly affecting its performance. It is deduced that the cloak is very narrowband, ideally operates correctly...
A family of dielectric resonator antennas, the supershaped DRAs, has been introduced in this communication. These DRAs exhibit wideband matching characteristics and broadside radiation. The cross section of the supershaped DRAs was described by means of a simple analytical expression depending on a set of six real parameters. By modifying these parameters it is possible to re-shape the antennas and...
In this paper we use a coordinate transformation to create a cloak that covers a triangular-shaped conducting object placed on a ground plane. A finite-difference time-domain (FDTD) algorithm that uses non-orthogonal mesh cells (NFDTD) is initially utilized to test the full cloak. Using the coordinate transformation method, we have designed a ground-plane cloak that is an approximate version of the...
The sub-cellular thin wire FDTD algorithm is modified and combined into a single FDTD method so that it is able to capture the SE performance of the enclosure with a number of geometrical and physical parameters changed, illuminated by an electromagnetic pulse. Then several methods to mitigate the coupling were introduced and investigated in detail.
This paper presents a detailed comparison of the results of a 3D FDTD numerical model and experimental measurements of the antenna response of a microwave tomography system. The FDTD algorithm uses the thin-wire approximation to model the antenna structure and a resistive voltage source is used to excite the signal. The algorithm was validated against experimental data obtained for an array of monopole...
The path loss between insulated dipole antennas in homogeneous human muscle tissue is investigated at 2.457 GHz and an in-body path loss model is derived. Simulations using the FDTD and the MoM methods show excellent agreement. Also, the low values of the deviations demonstrate an excellent agreement between the simulations and models.
A novel stretched-coordinate form of the CFS-PML has been introduced based on the introduction of auxiliary terms that satisfy distinct auxiliary differential equations (ADE). The formulation provides a more general form for representing the CFS-PML for time-dependent solutions of Maxwell's equations. It is found that the method is equal in effectiveness and efficiency as the CPML for FDTD simulations,...
Determining the optimal location for an antenna on a platform is limited by the humans involved. Best guesses are based on previous experience and rules of thumb. As platforms become more complicated, determining the placement for antennas becomes an increasing challenge. This paper looks at XFdtd's, a finite-difference time-domain solver, implementation of a genetic algorithm (GA) for its effectiveness...
This paper presents the implementation of Mur first order absorbing boundary condition (ABC) in efficient algorithm for 3-D alternating direction implicit finite-difference time-domain (ADI-FDTD) method. The Mur ABC is formulated in compact matrix form by conforming to the ADI generalized splitting formulae. The reflection coefficients for both conventional and efficient 3-D ADI-FDTD with Mur ABC...
Integrated circuits are ever-increasing in complexity while also shrinking in size. Further, ultra mobile devices are ever-increasing in functionality while also becoming more compact in size. The goal of this work is to support these trends by computationally studying electromagnetic compatibility issues both on a device level, as well as on individual component level, since these issues are beginning...
This article demonstrated the effectiveness of a novel FDTD source called Huygens source. The source uses a generalized TFSF implementation and enables straightforward FDTD unidirectional subgridding with tremendous savings in CPU time and memory consumption. Furthermore, the incident field can be provided by other numerical EM tools like MoM and the new FDTD Huygens sources acts as a powerful hybridization...
In this paper, we validate the aforementioned technique as a means for lattice truncation of different types of media. It is shown through two numerical examples that the method is applicable to both conductive and dispersive media, presenting numerical errors comparable to those of PMLs. Also, it maintains stable performance in cases where conventional absorbers fail to function satisfactorily.
This paper uses a method to compute the kernel needed for dispersive scatterer computations numerically. FDDM works by substituting a Z-domain finite difference approximation for the transform variable in the Laplace transformed kernel. The inverse Z-transform of the result is the FDDM kernel. The method described here computes the inverse z-transform directly by integrating in the complex z plane...
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