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This paper explores an influence of conductive layer geometry on electrical parameters of ferrite electromagnetic interference (EMI) suppressor, which consists of conductive layer in ferrite monolithic structure. Near ferrimagnetic resonant frequency, component has maximal impedance and efficiently suppresses noise. In order to achieve better suppression (i.e., larger impedance), conductive layers should be longer. Nevertheless, longer conductive lines introduce parasitic capacitance, which causes the maximal impedance frequency shift. Because of that, the frequency range where component can be used for efficient EMI suppression is shifted towards lower frequencies, and designing process should be very careful. In this paper, we present simulation of frequency dependent impedance for different geometry parameters of conductive layer. Results for the inductance and the maximal impedance frequency shift of the proposed EMI suppressors are presented in the range 1 MHz-3 GHz. Proposed EMI suppressors were experimentally tested using Agilent 4287A RF LCR meter. Comparison of simulated and measured values of impedance shows a good agreement.

Self-ordered arrays of Ni, Ni(50) Pd(50), and Ni(78) Pd(22) nanowires were synthesized by simultaneous electrochemical deposition of Ni and Pd components into porous templates of anodic aluminum oxide using alternating current. This paper is focused on the interplay of structure and chemical composition of Ni and Ni-Pd bicomponent nanowires arrays and the peculiarities of its magnetic anisotropy.

As the dc bias flows through a ferrite chip surface mount device (SMD) inductor, it tends to premagnetize the core and reduce its inductance and impedance. It is observed that this drop is especially emphasized when the dc current exceeds the safety limit given by the manufacturer. Therefore, it is necessary to investigate and predict the degree of electrical characteristics degradation as well as the dependence of the core losses on core temperature. In this paper, a measurement technique for the investigation of the influence of dc bias on the electrical characteristics of SMD inductors (i.e., inductance, resistance, Q factor, and real and imaginary part of impedance) for printed circuit board applications is presented. Analysis is based on the model of the SMD inductor, which can be presented as a two-port equivalent circuit with intrinsic and extrinsic parameters. For calculation of the parameters of the SMD inductor, extracted from measured S-parameters using vector network analyzer, the in-house software tool IndCalc was used.

In this paper, we present the modeling, fabrication, measurement techniques, and characterization results of multilayer miniature coplanar waveguide (CPW) meander-type inductors for high-frequency applications. Detailed procedure of the fabrication process based on using ink-jet printing technology is given. Silver nanoparticle ink that contains 20 wt% of silver was printed on a flexible polyimide foil 50 mu m thick in one, two, and three layers. It is shown that multilayer CPW inductors have improved performance. Almost two times better Q-factor value was achieved. This is an encouraging result for multilayer printing in ink-jet technology.

In this paper, we present the modeling, fabrication, measurement techniques, and characterization results of multilayer miniature coplanar waveguide (CPW) meander-type inductors for high-frequency applications. Detailed procedure of the fabrication process based on using ink-jet printing technology is given. Silver nanoparticle ink that contains 20 wt% of silver was printed on a flexible polyimide foil 50 mu m thick in one, two, and three layers. It is shown that multilayer CPW inductors have improved performance. Almost two times better Q-factor value was achieved. This is an encouraging result for multilayer printing in ink-jet technology.

In this paper, we present the modeling, fabrication, measurement techniques, and characterization results of multilayer miniature coplanar waveguide (CPW) meander-type inductors for high-frequency applications. Detailed procedure of the fabrication process based on using ink-jet printing technology is given. Silver nanoparticle ink that contains 20 wt% of silver was printed on a flexible polyimide foil 50 mu m thick in one, two, and three layers. It is shown that multilayer CPW inductors have improved performance. Almost two times better Q-factor value was achieved. This is an encouraging result for multilayer printing in ink-jet technology.

In this paper we present an improved model of the multilayered T-type electromagnetic interference chip LC filter for printed circuit board applications, and an improved measurement technique for characterization of such devices. Electrical parameters measurements of the same LC filter can vary for different measurement types. Because of that, we have developed new adaptation microstrip test fixture on printed circuit board for vector network analyzers' measurements of surface mount devices with three terminals. Two commercially available components, multilayer T-type LC filters, are measured and characterized using a vector network analyzer. The comparison of measurement data and simulation values of electrical equivalent circuit and electromagnetic model for two LC filters is further presented. The new improved model of T-type LC filters has provided better agreement between measurement and simulation.

The goal of this work was to investigate the behavior of a ferrite electromagnetic interference (EMI) suppressor when placed in a real surrounding. Electrical parameter measurements of the same EMI suppressor can differ for different combination of instruments and test fixtures. For that reason specially designed microstrip test fixtures are developed for the vector network analyzer (VNA) measurements. This paper describes the measurement technique, parameters extraction, and characterization of ferrite EMI suppressors for printed circuit board (PCB) applications. Two commercially available components, multilayer chip SMD inductors in a ferrite body, are measured and characterized using a VNA E5071B and developed adaptation test fixture on PCB board. These measurements describe intrinsic and extrinsic parameters of the components and their behavior. If the components are mounted on the PCB, i.e., in a real environment, then the two-port EMI suppressor model with extrinsic parameters has to be used at RF frequencies. The comparison of measured and datasheet values is further presented.

The unknown current distribution (UCD), self and mutual admittances (impedances), grounding impedances of coupled vertical mast antennas (CVMA) on a conducting halfspace are presented in this paper. The UCD is determined by numerical solving of the system of integral equations of two potentials (SIE-TP), The simplified Sommerfeld's expressions for potentials (the Hertz vector potential and electric scalar potential) are used for establishing the SIE-TP, The influence of the earthing systems on the antenna characteristics are adequately treated.

The unknown current distribution (UCD), self and mutual admittances (impedances), grounding impedances of coupled vertical mast antennas (CVMA) on a conducting halfspace are presented in this paper. The UCD is determined by numerical solving of the system of integral equations of two potentials (SIE-TP), The simplified Sommerfeld's expressions for potentials (the Hertz vector potential and electric scalar potential) are used for establishing the SIE-TP, The influence of the earthing systems on the antenna characteristics are adequately treated.