Buscar recursos académicos

This paper proposes an approach to estimate the probable location of maximum exposure to electromagnetic fields associated with a radiocommunication station, based only on information of antenna's height, half-power angl...

Abstract The theory of multiconductor transmission lines is based on the principle of superposition. According to this principle, any electric or magnetic field can be represented as the sum of individual electric or mag...

Abstract This paper presents an equipment dedicated to the monitoring of synchronous generator through the measurements of the external magnetic field time derivative. The equipment uses a methodology which can be an add...

The concern about the health risks that wireless technology can provide has grown globally thanks to the growing use of the devices by the population, by the finding that the public exposure to EMFs from the devices can ...

Abstract Electromagnetic problems with moving structures are considered. For objects moving at a uniform velocity, the most popular technique used in the literature consists of a change of the reference frame and the uti...

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 Nowadays, communication and networking technologies are essential for Oil & Gas industries in order to guarantee reliability, safety and low costs in the producing process. Information access and commands and se...

This paper describes a model for the analysis of multilay-ered chiral structures containing planar electric and magnetic scattering elements of arbitrary shape, illuminated by an elliptically polarized plane wave. The pa...

This work describes the design and optimization of a printed circuit board containing a rectangular half-loop coil designed to apply radio frequency signals on micrometric diamond crystals. The structure was optimized to...

Abstract An attempt has been made to present a new device which will function as a highly efficient SDR (Single Drift Region) P+-N- N+ IMPATT diode utilizing the advantages of a junctionless field effect transistor. The ...

AbstractThis paper presents an inversion methodology through weighted least squares to obtain the electrical parameters for the soil of a typical mid-western region in Brazil using the model based in the formalism of the...

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). ...

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...

This work studies a Transcutaneous Energy Transmitter (TET) which uses electromagnetic fields to transfer power from outside the body to an artificial organ in the body, working like a high frequency transformer with the...

Abstract An alternative theoretical approach is presented for improving the understanding of the scattering properties of simple negative-index and plasmonic spheres. The Mie scattering coefficients are broken up into tw...

Abstract In this study, a rib waveguide is used in the design of a plasmonic sensor. The structure consists of a dielectric substrate constituted of tantalum pentoxide (Ta2O5). On top of this substrate, a superstrate wit...

Abstract Recently, many machine learning techniques have been presented to detect brain lesions or determine brain lesion types using microwave data. However, there are limited studies analyzing the location of the lesio...

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 Solar cells integrated with antennas have aroused scientific interest as an attractive energy source alternative in low power devices for IoT and Wireless Sensor Network applications. Since the space for all com...

This paper presents an evaluation of the phase shifting excitation and load effects in a Transmission Line Exciting Chamber. This chamber is suggested as an alternative for immunity tests because of the restrictions rela...

Abstract An accurate modeling of materials is essential to obtain reliable results in fields calculation. The Jiles-Atherton approach is widely used for modeling the magnetic hysteresis and depends on its set of five par...

Abstract In this work a Finite-Difference Frequency-Domain (FDFD) propagation method for complex urban environments is proposed. The formulation starts from the discretization of the Helmholtz equation for the magnetic f...

Abstract This paper presents the propagation channel characteristics of a digital TV single-frequency network (SFN) obtained by carrying out field measurements using two synchronized transmitters. The measurements are pe...

A recursive procedure is applied to the measured near-field profiles of buried optical waveguides recorded in a lithium fluoride (LiF) crystal by femtosecond laser pulses in order to estimate the core dimensions and the ...