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In this paper the properties of an ensemble of Swiss rolls are investigated. By fitting an analytical solution to the results of the simulation, the macroscopic permeability and permittivity are determined. For the simulations, boundary integral equations are used, discretized by the method of moments (MoM), which leads to a set of linear equations. To reduce the CPU-time needed to solve the set of...
In this paper, we have outlined a novel procedure for accurately designing and optimizing wideband, cavity-backed Archimedean spiral antennas. We have used a precise transmission-reflection based waveguide measurement technique to accrately characterize a set of commercially available absorbers. From the complex permittivity and permeability data thus obtained, we designed a multi-layer composite...
The design and optimization of high-frequency electronic systems such as antenna and microwave devices requires scanning and searching over various design parameter spaces that include frequency, material permittivity, permeability, or excitation (i.e., scan angles). Such sweeps require repeatedly solving the computational model (FEM or BEM) at various different parameter value combinations, leading...
This paper investigates the benefits of high permittivity and permeability RF materials on electromagnetic interference (EMI) performance of integrated circuit (IC) heatsinks. An analysis of lossy materials using Finite-Difference Time-Domain (FDTD) simulations is presented and findings are supported by experimental measurements carried out in both reverberation chamber (RC) and Semi-Anechoic Chamber...
This paper presents complex permittivity and permeability measurements and reflection analysis of a selection of iron-loaded absorbing materials. A precise transmission-reflection based waveguide measurement technique was used to accurately characterize the materials in the 2 to 40 GHz frequency range. Based on the individual absorption spectra the materials were combined to form a composite structure...
Left hand materials are composite medium which have simultaneously negative permittivity and permeability. The tradition methods to artificial fabricate left hand materials are static, so the experiment devices to verify them are relatively simple. A novel approach is presented to synthesize left hand materials with negative refractive index in microwave band by incorporating periodic metallic wire...
This paper describes a setup for measurements of the permittivity and the permeability at temperatures from room temperature up to 1000°C using a single rectangular waveguide. The hardware design of the setup that can handle these temperatures is developed and described. Measurements on a NiZn ferrite sample are performed in order to evaluate the performance of the setup and the procedure that is...
Recently introduced concept of active non-Foster metamaterial is reviewed with an emphasis on the counter-intuitive background physics. A basic building block of this active metamaterial is an active `tank circuit' that contains both conventional reactance and non-Foster negative reactance. It is shown that active metamaterial is stable if equivalent permittivity or permeability is arbitrarily small...
In the paper measurements of the magnetic properties of powdered nanostructured alloys - Fe73,5Cu1Nb3Sil3,5B9 (Finemet) were presented. Measurements were realized in the coaxial line in the frequency range 0, 2 - 10, 2 GHz. The new technique for measuring of permittivity and permeability of powdered materials was developed. The obtained data was compared with data of powder received from milling of...
This paper introduces a new characterization method for on-wafer magnetic dielectric thin film materials. For this class of materials, it is necessary to determine both εr and μr from the measured characteristic impedance and propagation constant of transmission lines. This new method uses two transmission lines of the same length but with different characteristic impedances. Simulated results are...
Material constants of artificial dielectrics are measured using the waveguide reflection and transmission methods for the first time. Relative permittivity has taken the value of around 10 in good agreement with the simulated value for the most densely packed spherical metal particles. Relative permeability, on the other hand, has been found less than unity, due to Lentz law as was expected by the...
The present report branches out into two related topics. The first is concerned with the implementation of a computational modeling to predict the behavior of electromagnetic materials in confined environment by using electromagnetic three-dimensional simulation. The second topic re-examines the Nicolson-Ross-Weir mathematical model to retrieve the constitutive parameters (complex permittivity and...
Solution of matching problem for pear-shaped monopole antenna (PSMA) for personal communication systems (PCS) is proposed by introducing some matching device. The proposed antenna utilizes the advantages of the simple design to match antenna structure with feeding cable and free space. PSMA contains a pear-shaped metallic core covered by a thin dielectric layer, which keeps antenna size small. PSMA...
In this paper, a method to simulate the electromagnetic parameters of materials with quasi-periodic microstructures is presented and the parameters of fly-ash cenosphere particles are simulated. Results prove that the permittivity and permeability by this method coincide with that from the Bruggeman formula. By applying this method, it is possible to propose some strategies to improve the current...
We have clarified that the dissipation loss in artificial dielectrics is divided into two components, and how they depend on the dimensions and alignment of metal strips, and the signal frequency. One of the results has been applied experimentally to reduce the dissipation loss. Though it is a preliminary result, improvement has been appreciate the support of Research Center for 3.1 qualitatively...
In this paper, we introduce a new AMC structure which is implemented using an ideal homogenous material of constant permittivity and constant permeability, and we derive rigorous equations and analyze this structure theoretically. A dipole antenna on the AMC is designed and some notable characteristics are presented.
Effective antenna miniaturization is a challenging problem due to the inevitable trade-off between the size and the performance of the antenna due to the fact that antenna performance is bound with the fundamental limits based on the size of the antenna. Antenna miniaturization is also a critical issue since the key component determining the size of a mobile device is usually the antenna. Recent studies...
Next generation microwave devices require to be multifunctional for efficient, cost effective operation in light weight, low volume structures. A miniature tunable negative index metamaterial phase shifter and an ultra wideband phased array antenna have been designed using ferrite materials. Negative permeability ferrite material in combination with negative permittivity of plasmonic wires produces...
The use of the molded interconnect device technology combined with the laser direct structuring technology exhibits the potential of designing electrical and mechanical components on three-dimensional surfaces to increase functionality, level of integration and to reduce costs. When taking advantage of these technologies especially in the design of RF devices, a precise knowledge of the electromagnetic...
This work discusses the validity of the effective-medium interpretation of the multilayer negative-refractive-index transmission-line (NRI-TL) metamaterial superlens using supporting simulation and experimental data. The uniqueness of its extracted effective permittivity and permeability is verified through a comparison of simulation data for lenses of different thicknesses, and simulations of negative...
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