Advanced Electromagnetics (E-Journal)
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Losses Approximation for Soft Magnetic Composites Based on a Homogenized Equivalent Conductivity
No full textSoft magnetic composites (SMC) are a promising alternative to laminated steel in many Electrical Engineering applications. This is largely owing to their low level of eddy current losses. The electromagnetic behavior of SMC in electromagnetic devices cannot be easily predicted using standard numerical techniques such as the finite element method, mostly due to the computational cost required to model the material microstructure. Another difficulty lies in the high property contrast between the matrix and the inclusions. In this paper we propose a homogenization strategy to define the equivalent electromagnetic properties of SMC. For components made of SMC, the equivalent conductivity and permeability can be determined. These equivalent properties can be used to calculate eddy current losses or introduced into structural analysis tools to design electromagnetic devices
A Hybrid Technique Using Combinatorial Cyclic Difference Sets and Binomial Amplitude Tapering for Linear Sparse Array Antenna Design
No full textReducing system complexity and cost in synthesizing a sparse array antenna design is a challenging task for practical communication systems, such as radar systems and space communication. In this paper, a hybrid technique to synthesize a linear sparse array antenna design is described. This technique is developed using two methods. The first method is a combinatorial approach that applies cyclic difference sets (CDS) integers to significantly reduce the number of antenna elements. The approach and procedure used to apply the new CDS method to configure a linear sparse array, with significant reduction of the spatial antenna dimension, is described. The second method, applied to the array result of the first method, is amplitude tapering using a binomial array approach to reduce the sidelobes level (SLL). The simulation and measurement results of the sample sparse array design showed that the SLL was reduced in comparison to the sparse array design using only the combinatorial CDS method
Design and Analysis of Novel Fractal Linear and Planar Array Antennas for Satellite Applications
No full textThis article proposed a new geometric design methodology for the systematic expansion of fractal linear and planar array antennas. Using this proposed geometric design methodology any deterministic polygon shape can be constructed. In this article, two element fractal linear and triangular array antennas are examined using proposed methodology up to four iterations of two expansion factors. Due to the repetitive nature of the proposed geometric design methodology, both linear and planar fractal arrays shows multi-beam behavior with excellent array factor properties. The behavior of the proposed arrays shows better performance than linear and planar fractal array antennas generated by concentric circular ring sub array geometric generator. Triangular planar fractal array of expansion factor two at fourth iteration achieved a single valued beam width of 3.80 with -31.6 side lobe level. The suggested fractal arrays are analyzed and simulated by MATLAB-13 programming
Patch Antenna based on a Photovoltaic Cell with a Dual resonance Frequency
No full textThe present work was to use photovoltaic solar cells in patch antenna structures. The radiating patch element of a patch antenna was replaced by a solar cell. Direct Current (DC) generation remained the original feature of the solar cell, but additionally it was now able to receive and transmit electromagnetic waves. Here, we used a new patch antenna structure based on a photovoltaic solar cell. It was then used to collect photo-generated current as well as Radio Frequency (RF) transmission. A mathematical model which would serve the minimization of power losses of the cell and therefore the improvement in the conversion efficiency was studied. A simulation allowed analysing the performance of the antenna, with a silicon material, and testing its parameters such as the reflection coefficient (S11), gain, directivity and radiated power. The performance analysis of the solar cell patch antenna was conducted using Advanced Design System (ADS) software. Simulation results for this antenna showed a dual resonance frequency of 5.77 GHz and of 6.18 GHz with an effective return loss of -38.22dB and a gain of 1.59dBi
Reliability Study of Mechatronic Power Components Using Spectral Photon Emission Microscopy
No full textIn this paper, we present one of the most important failure analysis tools that permits the localizing and the identification of the failure mechanisms. It is a new spectral photon emission system, enabling to localize the failure, and quickly get the photon emission spectra that characterize the failure with high resolution. A diffraction grating is used as a spectrometer in the system. Application results on mechatronic power devices such as HEMT AlGaN/GAN and SiC MOSFETs are reported
Inverse Scattering in a Multipath Environment
No full textIn this contribution an inverse scattering problem is ad- dressed in a multipath environment. In particular, multipath is created by known ”extra” point-like scatterers (passive elements) expressely deployed between the scene under in- vestigation and the source/measurement domains. Through a back-projection imaging scheme, the role of the passive elements on the achievable performance is shown and com- pared to the free-space case. 
Metric entropy in linear inverse scattering
No full textThe role of multiple views and/or multiple frequencies on the achievable performance in linear inverse scattering problems is addressed. To this end, the impact of views and frequencies on the Kolmogorov entropy measure is studied. This way the metric information that can be conveyed back from data to the unknown can be estimated.
For the sake of simplicity, the study deals with strip scatterers and the cases of discrete angles of incidence and/or frequencies. 
Extremely Low Frequency Electromagnetic Field (ELF-EMF) and childhood leukemia near transmission lines: a review
No full textThis article presents a systematic review of most cited studies from developed countries those shed light on the potential relation between childhood leukemia and extremely low frequency electromagnetic field (ELF-EMF). All the findings of articles critically segregated as per some neglected parameters like number of samples, exposure duration, frequency range, distance from the radiation sources, and location during measurement of magnetic field density near power lines. Literature of major 50 studies are divided according to pooled analysis / meta-analysis, residential zone assessment and case-control studies
Investigation on Microstrip Filters with CSRR Defected Ground Structure
No full textThis paper consists the design studies of complementary split ring resonator (CSRR) defected ground structure (DGS) microstrip filter with low insertion loss in the passband and high rejection in stopband with a comparison of various CSRR-DGS structure has been proposed. Various parameters of microstrip filters have been studied with CSRR-DGS such as roll off rate, bandwidth, effective inductance and capacitance. On the basis of these studies, microstrip low-pass, bandpass and dual-band bandstop filters have been designed and realized with enhanced properties of filters
Strain Effect Study on Mode Field Diameter and Effective Area of WII Type Single Mode Optical Fiber
No full textIn this article, the effect of strain on mode field diameter (MFD) and effective area (Aeff) in a modern multilayer WII type single mode optical fiber is investigated. The modal analysis of the fiber structure is based on linear polarized (LP) approximation method. The simulation results depict that both mode field diameter and effective area grow as a result of increment in tensile strain. The overall effect is observed in a slight rise in quality factor (Qf) of the fiber. Likewise, enlargement in amplitude of compressive strain leads to decrement in MFD and Aeff. However, among the optical and geometrical parameters of the fiber structure, Δ has the most considerable impact on both MFD and Aeff variation whilst R1 shows the least effect. In other words, any shift in the value allocated to Δ results in substantial change in the MFD and Aeff alteration due to strain. To eliminate this effect, the higher amounts for Δ are preferable which is related to the layering structure of the WII type optical fiber