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Self-affine property of a modified multifractal Cantor geometry is exploited to design frequency selective surfaces (FSS) with multiband response. The main advantage of the proposed structure is to design multiband FSS w...

Abstract Normally the physical dimensions of the taper transition that realizes the impedance matching between the impedance of the feeding line built in microstrip line technology and the impedance of the component buil...

The use of wireless local area networks, called WLANs, as well as the proliferation of the use of multimedia applications have grown rapidly in recent years. Some factors affect the quality of service (QoS) received by t...

In this paper a novel approach based on the Real coded Genetic Algorithm (RGA) is proposed to improve nulling performance as well as suppression of Side Lobe Level (SLL) of a Time Modulated Linear Antenna Arrays (TMLA). ...

This work deals with numerical techniques to compute electrostatic fields in devices with rounded corners in 2D situations. The approach leads to the solution of two problems: one on the device where rounded corners are ...

Abstract This article presents the development of an inclinometer device based on a Mach-Zehnder interferometer considering the effects caused by temperature variations. It was demonstrated the operation of a LPG-taper s...

The quality of the optical fiber infrastructure is directly related with the strength of the fiber polymer coating. In this work we have studied the effect of maritime environment in the aging of optical fibers. The resu...

Abstract The present work aims at the application of different optimization strategies in the electromagnetic analysis of the Variable Reluctance Motor (VRM) through Finite Element (FE) simulation. Two case studies are i...

Abstract A good wireless network design depends on technical and financial viability and a number of other criteria that must be met. Following the emergence of new technologies and services, such as 5G transmission and ...

Abstract In this work, we investigated the path loss (PL) profile of the outdoor radio channel in the 800 MHz band for the Icaraí region in the city of Niterói. This frequency band has recently been reserved by the bra...

Abstract In this paper, a configuration of a passive Q-switched Erbium-doped fiber laser (EDFL) using a Lutetium Oxide (Lu2O3) thin film as a saturable absorber (SA) is experimentally implemented to generate high pulse e...

Abstract In this paper, it is presented a general optimization methodology for improving empirical models predicting Okumura-Hata, Cost-231, ECC-33, and Egli using Genetic and Differential Evolution Algorithms. The metho...

Abstract This paper describes a method using Quantum Particle Swarm Optimization to obtain a broadband frequency invariant pattern for synthesis of nonuniformly spaced linear array of isotropic antennas. Two cases relate...

AbstractThis article proposes a deterministic radio propagation model using dyadic Green's function to predict the value of the electric field. Dyadic is offered as an efficient mathematical tool which has symbolic simpl...

Abstract This paper presents a compact and planar reconfigurable filtenna for application in Wireless systems. The filtenna is composed of a UWB circular antenna and a filter with two trapezoidal resonators. The filter i...

In this article, a dual band annular ring patch antenna is theoretically investigated using the equivalent circuit concept.Two symmetrical rectangular notches are etched in radiating ring patch with respect to feed point...

In this paper, Specific Absorption Rates (SAR) inside the human head and hand have been analyzed for a handheld mobile phone operated at GSM 900 band. Both the head and hand are modeled electrically using Digital Imaging...

AbstractThe definition of parameters that characterize the radiation of electric and magnetic fields for antennas in the time and frequency domain on an unified representation is proposed. The formulation uses a straight...

Abstract In this work, a new concept of planar resonator technique for measurement of liquid mixture permittivity is proposed, designed, and implemented using a Sixteen-Mode Substrate Integrated Waveguide (SMSIW) technol...

Abstract A methodology based on spectral analysis for localization of multiple partial discharges in dielectric region of hydro-generator coils is proposed. This pinpointing of multiple discharges aims to provide means f...

Abstract Substantial modifications have been made to the expressions for calculating distance factor and extrapolation techniques in the latest ITU-R P.530-14. However, its performance has not been rigorously evaluated i...

In this paper, single and dual band EBG structures for wider bandwidth are proposed. In each of the discussed EBGs, a metallic patch of regular geometry is chosen for the unit element. The patch is further modified by cu...

Abstract This paper presents the influence of different sizes of carbonyl iron particles on the reflectivity measurements of Radar Absorbing Material (RAM). The electromagnetic characterization was performed with a vecto...

Abstract This paper describes a new design methodology for reconfigurable printed circuits with limited size, using an improved hybrid particle swarm optimization (HPSO) algorithm, reducing the search space by the defini...