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The continual trend of miniaturization and increasing complexity in the field of Radio Frequency (RF) devices poses a challenge for today's manufacturing technologies. The possibility of miniaturization of RF components with Molded Interconnect Devices (MIDs) is very attractive. However, electromagnetic properties of MID substrates based on polymer materials and behavior of RF basic components designed...
In this work, three dimensional finite element modeling is used to compute the electric field distribution on a spacer cable system. The electric field for different compatibility test configurations is computed in order to show the differences observed between the use of single phase and three phase power supply to energize the test setup. According to the simulation results, the electric field enhancement...
Measurement methods of complex permittivity of dielectric materials (from 20 GHz to 3 THz are introduced. The dielectric properties of a liquid crystal polymer were not affected by environmental conditions, thus liquid crystal can become a candidate for insulating materials used in THz communications.
Radiation-cured epoxy and acrylate-based materials are used in a number of applications where curing under ionizing radiations is preferred to the classical thermal curing process. Because mechanical properties are often the key features in these applications much less attention has been paid to their electrical properties. We report on the dielectric properties of two classes of radiation-cured materials...
Attenuation of common mode currents is of great relevance for all electronic components and systems, since these currents often give rise to unintended and undesired radiation. Here, usage of common mode chokes and ferrite cores is well established. In this work a novel damping method is described. By using dissipative resonant cavities a relatively high attenuation can be obtained in a more or less...
The electric and magnetic properties of the magnetically soft Fe-Si-B-Nb-Cu alloy (Finemet), as a candidate on the absorber at microwaves, have been studied in the frequency range from 0.2 to 10 GHz. Measurements were achieved with the use of the coaxial line technique, where the scattering parameters at broadband frequency range were determined. In this method, using the signal flow graph representation,...
A new strategy for preparation of nano-sized barium titanate (BaTiO3) particles was applied by using: layered (tetramethyl)ammonium titanate, barium acetate and tetramethylammonium hydroxide. An addition of barium salt to aqueous layered titanate colloids leads to a precipitation phenomenon by which barium titanate precursor was obtained. The mechanism of this reaction is based on ions exchange which...
The effect of gamma-ray irradiation on relative permittivity, ac conductivity and dielectric loss tangent of epoxy resin and polyethylene has been investigated. Laminated samples were irradiated by 60Co gamma source at room temperature in air with a dose rate of 10 kGy/h and the total dose were 100 kGy and 1000 kGy. The dielectric properties were measured by using a Precision LCR Meter (Agilent E4980A)...
Two different types of instrumentation have been utilized to characterize thin film samples. New techniques have been developed so that the dielectric permittivity values can be determined accurately at microwave as well as at millimeter wave and terahertz frequencies. A specially designed slotted cavity for X-band microwave measurement has been employed with a vector network analyzer to overcome...
This paper reports the experimental study on the frequency and stretch dependency of permittivity of a commercially available acrylic dielectric elastomer (VHB 4910) film. The procedure for preparing samples with different thickness using in-house developed uniaxially stretching device is described. Copper tapes are implanted on two opposite sides of a stretched elastomer film and permittivity of...
Averaging the permittivity and permeability functions at the location of a material interface has become the most popular method to enforce the field continuity conditions in finite-difference discretizations of Maxwell's equations. While this approach offers unparalleled simplicity, the global error performs poorly—worse than first-order accuracy—when the sign of the material functions changes across...
An important aspect in the development of any material characterization method is error analysis. As the necessity for non-destructive evaluation and quality assurance applications increase, free space material characterization methods along with error analysis of these methods will become imperative. A common approach for performing error analysis is the error propagation method. The error propagation...
A novel coaxial probe is developed for measuring complex permittivity of soils in-situ from 10 to 1000 MHz without taking soil samples. The dielectric constant and conductivity of soil is derived from step-frequency reflection taken inside a small freshly bored hole. As a result, permittivity at various depths with in-situ moisture content and soil texture can be obtained in the fields. A novel permittivity...
Permittivity and attenuation coefficient have an important role in a GPR survey. These are used as the key properties. The general values of these properties are fundamentally well known, however the values usually vary site by site, and accurate values are sometimes necessary for proper analysis. There is a characteristic phenomenon called the “zebra effect” in holographic radar images from the “Rascan”...
In this work we consider the enhancement of ultimate performance of semiconductor infrared detectors utilizing nanoplasmonics. To this purpose we analyze the application of transparent conductive oxides (TCO) as plasmonic material with the plasma frequency in the near infrared. We investigate the possibility to apply TCO nanoparticles for field localization embedded into a dielectric host. We consider...
This study aims to investigate the clinical outcomes of human brain dielectric properties in order to build a human-like brain phantom using simple material. This artificial intelligence human brain was developed according to the dielectric properties of a real human brain. The regions cover grey matter and white matter tissues. Elements used for phantom building demonstrate adequate internal consistency...
This paper refers to a new calibration method using phase cancellation for measuring the dielectric properties of biological tissues based on electrically small open-ended coaxial probe. The physical model experiments of three calibration methods are undertaken in a frequency range of 1-120 MHz, the results show that the phase cancellation method offers a clear advantage in the reliability, furthermore,...
To the our best knowledge, this paper presents combination of a rectangular waveguide cavity and closed-end conical coupling probes for characterizing the permittivity of solid material for the first time. The proposed test configuration was designed based on transmission/reflection method to operate at 2.4–2.5 GHz. The design methodology and simulation results are also provided. In order to calculate...
In this paper, measurement of relative permittivity and loss tangent of wheat grain in C-band of microwave frequency using cavity perturbation technique is presented. The technique is based on the measurement of transmitted power from the cavity at and off resonance. Details of sample holder (to hold the sample in the central region of cavity) is given and its' effect on the wheat's relative permittivity...
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