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In this paper, a novel layer shaping method to reduce far-end crosstalk (FEXT) noise in multiple microstrip lines was proposed. To reduce FEXT noise induced in adjacent microstrip lines, mushroom-shaped dielectric structure (MSDS) was created between the microstrip lines. The prototypes were fabricated using 3D printer to avoid increased complexity, and the effect of the proposed MSDS was verifiedfrom simulated and measured results.

Multilayer dielectric structure was widely used in radome design, electromagnetic target stealth and microwave/infrared beam combiner. In this paper, the microwave transmittance and transmittance bandwidth in multilayer dielectric structures was studied based on particle swarm optimization. The effect of different numbers of dielectric layers on transmittance bandwidth was analyzed. The results showed that the three-layer dielectric structure can significantly increase the transmittance bandwidth. By researching the effect of dielectric constant on the transmittance bandwidth, it was concluded that when the dielectric constant of the intermediate layer was about 2.2 ~ 3.3 times that of the outer layers or intermediate layer was air in three-layer dielectric structure, high microwave transmittance and wide transmittance bandwidth can be obtained. Based on above conclusion, a beam combiner composed of three dielectric layers was designed, and the thickness of each layer was optimized by particle swarm optimization algorithm. The average transmittance of designed beam combiner was more than 96.5% from 10GHz to 16.4 GHz over the incident angle range of 0° ~ 20°.

we investigate angular reflectance of dielectric multilayer structure that has a narrow resonant peak. The design of dielectric multilayer structure with peak respond in reflectance is presented. We demonstrate the increasing brightness and beam quality of wide-aperture laser due to the angular selective properties the dielectric multilayer structure. We analyze the characteristics of such structure and how to optimize layout of the layers. The peculiarity of proposed angular selective element is allowing the application as intracavity laser mode corrector.

Some approaches to solving the inverse problem of reconstruction of the permittivity profile of multilayer dielectric structure developed by Ukrainian authors are under consideration. A number of resonator constructions for permittivity measurements suggested by Ukrainian scientist are analyzed. Some ideas for subsurface probing data processing are under discussion. The information about some original microwave components and devices, which can be applied for obtaining measuring instruments, is presented.

The relationship between the eigen parameters of the periodic Bragg structure and the effective parameters of an equivalent homogeneous medium is considered. By the example of a layered dielectric structure, their relationship with the constructive parameters is examined and their dependence on frequency is analyzed. An approach which makes it possible to obtain physically consistent values of the effective permittivity and permeability of the Bragg structure is considered.

To consider a large and complex conducting or dielectric structure, an iterative physical optics method is proposed. The scheme is numerically and experimentally verified for a scattering and radome problems.

An approximation is derived for longitudinally inhomogeneous waveguides (LIW). Total reflections are adopted for a rough approximation through the tracking of the main reflected and transmitted fields in the multilayered dielectric structure. This approximation can be used to determine the thickness of layers of which the dielectric properties are known. Although the obtained thickness values are a rough approximation for the exact values, they provide a utility for iterative optimization algorithms for which the initial values are vital.

Measurements of the negative optical phase shifts of Ag/TiO 2 and Ag/SiO 2 bilayer films have been carried out with the modified walk-off interferometer. Appearance and monotonic rise of the phase shift anisotropy for p- and s-polarization by increasing incidence angle has been revealed experimentally. The results of measurements have shown rather good coincidence with theoretical calculations.

The spectra of hybrid EMSOs in the composite ferrite-dielectric structure based on single crystal BaFe 12 O 19 with the MDS in initial state were experimentally investigated. As it can be seen from Fig. 2 the fact of simultaneous hybridization of both MSOs modes ω 1 and ω 2 with DR electromagnetic mode one has been revealed. It should be emphasized that as the result of ω 1 and ω 2 interaction with DR electromagnetic mode the three quasi-electromagnetic modes are observed for the first time even at low external in-plane static biasing magnetic fields.

A technique for calculating the effective dielectric constant for a square loop FSS located in a layered dielectric structure was developed using conformal mapping techniques. This was accomplished by approximating the FSS as a set of two coplanar strips, for which a conformal map already exists. This method yields results comparable to those found through simulation, while having a shorter computation time. Furthermore, this method can be used for arbitrary square loop FSS designs and layered dielectric structures.

Multi-layer dielectric devices used for isolated power transfer and suitable for high frequency power applications (>100kHz) are proposed. Such devices were realized based on a four terminal multi-layer ceramic structure with barium strontium titanate and alumina layers. Some key advantages of these devices are a reduction in losses over conventional decoupling techniques and ease of manufacturing due to the planar design. The paper focuses on the design details, characterization and performance of the Multi-Layer Capacitive Isolation Devices (MLCIDs).

We present analysis and design optimization of passive UHF RFID (Radio Frequency Identification) tags for tracking automotive tires. The RFID tags are mounted on or embedded into tires to monitor their conditions, verify their history and track inventory. In this paper, we evaluated the performance of existing RFID tags designed specifically for tires. It is found that the current RFID tags do not operate well in the vicinity of adjacent tires. This is due to the tire's dielectric structure and metallic radial plies inside the sidewalls. These factors were also verified in simulation models. Recommendations for new tag designs will be provided at the meeting.

We here illustrate the ability of electro-optic sensors to perform electric field vectorial measurements. Thanks to their frequency response that remains flat over nine decades and to their measurement dynamics reaching 120 dB, these sensors are of key interest for many applications. Furthermore, due to their fully dielectric structure and to their millimetric size, almost no perturbation is induced on the electric field to be measured, even in the near field region. This paper is focused on high intensity pulsed electric field characterization in different environments such as water (bioelectromagnetism applications) or plasma (in-situ assessment of the electric-field associated to an electric discharge). The use of such technology for electrical equipments and energy lines monitoring is also investigated.

In this paper, we analyzed the distribution of energy flow for dielectric waveguide introduced as defect layers composed of dielectric circular cylinder array with de formed rhombic dielectric structure along a middle layer and investigated the influence of rhombic dielectric structure compared with deformed rhombic dielectric structure by using the propagation constants at the guided area for both TE0 and TM0 modes.

In this paper, accuracy of equivalent models for composite materials based on a multilayer lossy dielectric structure is discussed. Three different models are described. These models are based on scalar or incomplete vector measurements of coefficients S11, S22 and S21. Agreement between simulated values of the magnitude of the reflection and the transmission coefficient and the coefficients predicted by the models is investigated within range of frequencies 100 MHz to 20000 MHz. Magnitude errors of coefficients predicted by the best of the models is 2 dB for transmission and 6 dB for the reflection coefficient. These errors are valid for both polarizations (TE and TM) and range of angles of incidences from 0 to 60 deg.

An improved SIAD structure for planar microstrip circuits' miniaturization has been presented in this paper. This structure provides enhancement of both the permittivity and the permeability, and therefore achieves guided wavelength compression, leading to circuit size miniaturization. By proper design of the SIAD, power divider can exhibit an area reduction of 74%. By change the SIAD geometrical parameters, one may achieve more area reduction. The improved SIAD structure has the potential to miniaturize many planar component and antenna applications at low cost.

Simplified equations for calculating the total reflection and transmission from a multilayer infinite and finite dielectric structure are presented. These formulas are based on examining the reflected rays within such a structure and working out an explicit form where possible. The purpose of this study is to build a simplified simulator for ground penetrating radar.

Comparison of coherent and noise probing is described in order to formulate the criteria for characterization of materials on mm-wave and microwave frequencies. Double-layers dielectric structure having Fabry-Perot resonator properties is employed to develop accurate mathematical model and to predict transmittances for both coherent and noise illuminations. Experiments have proved the basic modeling predictions as well as the role of noise bandwidth in averaging process used in material characterizations.

The scattering behaviour of Sierpinski gasket based metallo-dielectric structure loaded over metallic targets is reported. RCS reduction is obtained for the structure with frequency about 9-11 GHz. Furthermore, we have presented a fitted linear equation to describe the relationship between reduction peak frequency vs permittivity. This may has application in stealth of aircrafts or ships and the design of frequency selective surfaces.

Presented in this paper are the results of ring hybrid metal-dielectric structure experimental investigation. Peculiarities of radiating slot and ring resonator interaction have been investigated. Constructs influence on energy characteristics has been shown.

The effects of left-handed materials (LHM) on frequency selective reflection characteristics of dielectric periodic structures are carefully investigated using a method which combines the multimode network theory with the rigorous mode matching method. It has been shown that the selective behavior of periodic structures can be modified by adding LHM layers above and below the periodic layer.

The guiding properties of strip dielectric waveguides are examining in connection with problems of high-technological multifunctional elements and radiating systems designing. The special emphasis attends to the optimum excitation of dielectric structure problem and to concordance problem. The experimental data allow to predict the possibility of designing the functional elements with high level of parameters, one of them (radiating system) were investigated.

The some results of numerical simulation for the Gel'fand-Levitan method of reconstruction of discrete profile of permittivity are presented. Some examples of noise influence and threshold application are considered. The method is based on spectral analysis of frequency data with generalized pencil-of-function method.

Considered in this paper are the properties of multielement modified hybrid metal-dielectric radiating structure with screen and cophasal slot radiators. It has been investigated how the shield from the rod side influences pattern formation in 8-mm waveband.

We use the simulated annealing (SA) method to find the global minimum of a cost function associated with scattering from a layered dielectric structure with rough boundaries. In the case of a two layer structure, even a simple implementation of the SA algorithm is capable of retrieving more parameters than is possible with local optimization methods. We discuss different strategies that can improve the performance of this algorithm for our purpose.

A novel CoWP cap integration technology for lower leakage current and improved dielectric reliability is proposed for porous low-k/Cu interconnects, NH3 plasma treatment before SiCN deposition reduces leakage current and improves dielectric reliability such as time-dependent dielectric break-down (TDDB) of CoWP capped Cu interconnects. The TDDB lifetime much longer than 10 years is obtained. Moreover, the leakage current less than IE-14A/mm is obtained by low-k top (LKT) dielectric structure combined with the NH3 plasma treatment. In addition, 10% lower RC product is obtained by the LKT structure with CoWP cap

The traditional approach to power transformer asset management is largely based on gas-in-oil analysis, wherein generation of specific gases and their levels are used to assess the condition of the transformer. The maintenance decisions that follows usually needs supplementary information like position of the fault within the transformer dielectric structure and realistic risk that poses in operating the transformer. It is well documented that acoustic emission based technique could serve to identify the position of the fault in the electrical apparatus. However, it is not widely known that some thermal faults could be detected and located using acoustic emission technique. This contribution demonstrates using practical case studies how on-line acoustic emission based partial discharge measurement technique could be used to detect transformer faults of thermal origin and also how it could help in managing scientifically transformer assets.

International audience; Solving electromagnetic scattering and radiation problems with moment methods or finite element methods over a large frequency band gives accurate results, but it is often too time-consuming. So we propose a fast auto-adaptive method to optimize the computational electromagnetics solver applied in the case of various radiating and dielectric structures. This method is able to generate the electromagnetic behavior of the antenna with a very few simulations over a broad frequency band.

Problems of reflectogram restoration and autocorrelation function of reflectogram restorations are considered. The method of minimum duration is modified for cases of spectra extrapolation onto lower and higher frequencies. Optimal values of work parameters of "generalized" functional of duration are found. Results of numeric simulation are presented for one-layered dielectric structure.

A plasma damage resistant hybrid (polyarylene ether (PAR)/SiOC) dielectric structure using the ultra low-k (ULK) films with k value of 2.2 was demonstrated for Cu dual-damascene (DD) interconnects. The reliability issues attributed to plasma process induced damage to ULK films were clarified and resolved. As well as ULK film selection with plasma damage resistance, insertion of a low-k buffer layer with k value of 3.0 between SiOC and PAE and damage restoration process using hydrophobic treatment were found to be most important factors for robust ULK process integration.

In this paper we present a new solution for externally RF coupled dielectric loaded accelerator. In this scheme, a separate TE-TM converter is used for RF coupling and a short tapered section is used for matching the RF into the dielectric accelerating structure. Advantages of this new design are there is no dielectric presented near the coupler, thus less prone to premature breakdowns; and it can be made into separate modules of coupler, matching and accelerating structures, this will simplified the dielectric structure development because only one set of couplers is required for a defined RF frequency but with many different dielectric structures. An example of X-band 11.424 GHz coupler and dielectric accelerating structure is obtained via EM simulations. Based on the simulation results, a set of coupler, matching and dielectric structures were fabricated. We present bench measurement results and its comparison with the design.

Electrodynamic properties of open resonator with metal-dielectric structure have been experimentally investigated. The resonator can be used at creation of new models of selective devices and devices of EHF-electronics.

We will report one of the first studies on an organic LED (OLED) with a novel substrate structure. This structure consists of periodic dielectric structure as a light scattering media and reflects the waveguided light toward the direction vertical to emissive surface of devices. By using these structure, we expect a large increase in apparent external electroluminescence efficiency. We shows an OLED with a novel device structure. This device consists of a conventional OLED device vacuum-deposited on a flat substrate (emissive part) and a scattering substrate.

Discusses the problem of excitation of the considered dielectric structure for longitudinal (oriented along the axis of the waveguide) given currents. The present paper is devoted to building the Green's functions of magnetic and electric types for the sections of rectangular waveguides with three-layer longitudinally-inhomogeneous filling excited by such currents.

The failure of a simple dielectric structure at voltages much lower than design expectations, and in an intolerably short operating time, presented an opportunity for this study to be made at the Lawrence Radiation Laboratory, under contract with the Atomic Energy Commission.