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This paper describes test cells for electromagnetic characterization of materials in the frequency range from 5 Hz to 1000 MHz, which were developed at SIQ in the past 3 years as a part of EMINDA EMRP Project. Test cells are used for traceable measurements of different electromagnetic properties of bulk solid materials. Traceability of measurements is assured using characterized reference samples...
A simple method is presented to extract the material characteristics from the scattering parameters in the frequency domain. The method is based on “transmission” measurement data only and can give the complex permittivity and/or the absorption and refraction index via easy arithmetic operations with closed-form formulas. Therefore, a parametric error analysis will be feasible for metrological aspects...
In this work an ultra-wideband wire antenna was designed and fabricated for transmitting/receiving signals to/from inside the human body. The antenna provides high gain and thus high field intensity in its broadside direction; hence, a high energy density wireless can be established with the inner body. The proposed antenna operates in the frequency band of 3–10 GHz with an impedance of 200 Ohms in...
A technique to extract the electromagnetic properties of conductor-backed absorbing materials is introduced. The sample is first placed into a waveguide, completely filling its cross-section. Then a portion of the sample is fit into a reduced-step guide. The two measured reflection coefficients provide sufficient information to obtain both the complex permittivity and permeability of the sample. The...
This work demonstrates the use of genetic algorithms (GA) to transform the traditional free space characterization process into an optimization process. The basis of the process is to compare the measured reflection coefficient to the reflection coefficient computed by the GA. The GA computes the reflection coefficient using candidate solutions of the permittivity and permeability and the Fresnel...
Estimating the contact resistance and losses of Carbon-Nanotubes based devices is a challenging task. This work presents an effective model to calculate the contact resistance of single-walled carbon nanotube-based RF devices. The model realistically incorporates operational parameters beyond the quantum limits and it makes it feasible to implement the model in commercially-adopted COMSOL simulators...
The mathematical truth associated with the simultaneous multiparameter measurement using reflection only sensors is that if there are n unknowns to be determined, we need at least n independent measurements to be able to solve even one of them. In this paper, multilayer medium technique is employed to produce the needed independent reflection coefficients for simultaneous nondestructive determination...
In this paper, we investigate the properties of a complex nonmagnetic material through the reflectance, where the permittivity is described by a mechanism model in which an unknown probability measure is placed on the model parameters. Specifically, we consider whether or not this unknown probability measure can be determined from the reflectance or the derivatives of the reflectance, and we also...
This paper attempts to show the effective porous-structure of the nanoporous-silica/epoxy composite for lower-permittivity insulating material by using numerical analysis. The theoretical analysis indicated that the reduction of electric field enhancement at delamination defect of electrode/epoxy interface by more than 25 % required the relative permittivity (εr) of less than 3.0 of nanoporous-silica/epoxy...
The icy satellites of Jupiter are known to host a water ocean beneath an ice shell. The ice penetrating Radar for Icy Moon Exploration (RIME) housed on board the JUpiter ICy moons Explorer (JUICE) mission is expected to probe the crust of Europa, Ganymede and Callisto up to a depth of 9 km. The main objectives of RIME are the detection of the relic Brittle-Ductile Transition in the ice shell of Ganymede...
We developed an analytical code to model electromagnetic fields in 3D in a stack of vertical transverse isotropic layers. This code is suitable to model low-frequency as well as high-frequency responses and it is expected to become available as an open source package in 2014. We give an overview of the code and use it to investigate the sensitivity of different Ground Penetrating Radar antenna configurations...
The complex permittivity and permeability are evaluated by rectangular waveguide measurement technique which is based on hybrid electromagnetic method and uses an iterative process to fit the calculated values to the measured data. The iterative process is investigated by virtual experiments, and the efficiency and robustness of the evaluation method is confirmed.
In this paper, experimental characterization and modeling of inhomogeneous materials from RF, mm-Wave to THz frequencies with emphasis on anisotropic materials including Liquid Crystal Polymers (LCP) and patterned silicon substrates using DT mesh are presented. Network-based broadband extraction of complex permittivity values and dissipation factors for various materials are discussed towards derivation...
Dielectric materials with high-K, low loss and high breakdown voltage are of great importance for a broad range of applications in modern electronics and electrical power systems. In this work, embedded capacitors were fabricated with BT/ER composites as the dielectric layer. The composites were modified with Cr Acac which reacted with epoxy matrix. The addition of PEG and Cr Acac enhanced the permittivity...
Antenna size has fundamental limits based on the frequency of operation and performance required. In the past, various methods have been developed to miniaturize antennas with limited success. Magneto-dielectric materials, however, have been reported as providing new opportunities for effective antenna size reduction in many recent studies. In this paper, a novel material characterization method which...
This paper is aimed at analyzing and discussing the key-role of the evolutionary optimization in EM device synthesis carried out within the recently developed System-by-Design paradigm. Towards this end, SbD models the design process as an eco-system of functional blocks (for the synthesis/analysis of each sub-part of the overall complex system) suitably connected to enable different trade-off solutions...
This paper handles a proposed algorithm of surface to air anti stealth technology for homeland security. The paper approach is anti stealth theory and it's application by using fuzzy logic control. the anti stealth is done by exposing stealth EM 3500 wave absorber with non lethal pulsed ND YAG 532 then the electric permittivity enhanced and consequently reflection. The application of surface to air...
Application of plasmonics in optical communications has recently attracted significant research interest in the hope of overcoming the big mismatch between the footprints of electronic and photonic integrated circuits. This hope is based on the unique properties of the plasmonic devices, such as the confinement of light into subwavelength dimension. which enables breaking the diffraction limit and...
This paper presents a simple waveguide measurement technique to evaluate the complex permittivity of a homogenous dielectric material. The dielectric sample is loaded in the transmission line rectangular waveguide WR90. The S-parameters of the waveguide are measured by Network analyzer and calculated as a function of the complex permittivity using theory of transmissions lines. Using the MatLab Optimization...
Design of a proximity coupled implantable planar inverted F-antenna (I-PIFA) is presented. It's to be operated in the Australian 900MHz ISM band (915–928MHz). This antenna, integrated to an existing Radio Frequency Identification (RFID) tag, will be implanted under the skin of rats for medical research. The main purpose of this wireless telemetry system is to transmit the extracted physiological signals...
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