Buscar recursos académicos

AbstractThis paper proposes a new topology of a 2-Stages Active Polyphase Filter (APPF) in MMIC GaAs technology. This new topology, named “radial”, allows a greater balancing of output signals phases and amplitudes, ...

Abstract This paper presents the optimization performance of non-uniform linear antenna array with optimized inter-element spacing and excitation amplitude using Particle Swarm Optimization (PSO). The aim of the proposed...

In this paper a truncated corner rectangular microstrip antenna (TCRMA) is analyzed in the presence of carbon fiber composite (CFC) material. Simplified carbon fiber composite models are proposed and the analyses are per...

Abstract We use the two dimensional finite element method (2D-FEM) in the frequency domain to characterize the transmission properties of 90°-bend periodic segmented waveguides (PSWs). We investigated the dependence of ...

A comparative analysis of two cylindrical complex-frequency-shifted perfectly matched layers (CFS-PML) absorbing boundary condition (ABC) for bi-dimensional (2-D) finite-volume (FV) simulations in the frequency domain is...

Abstract Numerical and experimental analysis of visible light communication (VLC) systems based on orthogonal chirp division multiplexing (OCDM) and orthogonal frequency division multiplexing (OFDM) are presented in this...

This paper presents a FEM analysis of a hybrid excitation brushless axial flux machine (HEBAFM) for traction electric vehicle purposes in order to compare with the results from an analytical method used to determine the ...

Abstract For vehicle tactical radio communications, positioning antennas along the structure is a complex task. In vessels, there are several radio systems installed operating from HF to SHF. Consequently, the antennas n...

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...

In this paper, a software for design and analysis of frequency selective surfaces (FSS) based on the equivalent circuit model is presented, with emphasis on teaching students in the interaction between FSS parameters. To...

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 In this paper we have presented the four new investigations using different structures of Photonic Crystal Fiber (PCF) for broadband communication applications and narrows down on the design which can provide la...

Abstract Microstrip filters are widely employed in radio fre-quency and microwave circuits due to their efficiency, easy fabri-cation, and compatibility with printed circuit board technologies. In this scenario, this wor...

Abstract This paper reports detailed propagation analyses of mm-wave indoor networks based numerical simulations of the wireless coverage and measurements of the propagation coefficient at 28 and 38 GHz. Additionally, ma...

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...

We present and analyze a 17.6-Tb/s DWDM optical transmission composed of 79 channels with 224-Gb/s RZ-DP-16QAM modulation format per-channel and coherent detection. A maximum reach of 678 km is obtained with an optical r...

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...

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 This article presents the analysis of a hybrid, error correction-based, neural network model to predict the path loss for suburban areas at 800 MHz and 2600 MHz, obtained by combining empirical propagation model...

Abstract This paper presents a radiopropagation algorithm based on a Ray Tracing (RT) technique that combines a modified multipath model for constant refractivity gradient profiles and the Uniform Theory of Diffraction (...

Abstract This paper describes an investigation of the possibility of using a new conductive ink, insted of copper clad laminates, in the manufacturing of microstrip patch antennas on glass and fiberglass substrates and o...

Abstract In this paper, a new multiband fractal frequency selective surface (MF-FSS) is proposed. The work presents a new fractal design methodology for FSSs with Swastika fractal patch elements. The proposed MF-FSS incl...

Abstract This paper originates from a practical experiment based on Mesh Networks. The promising results obtained from this experiment prompted us to discuss in greater depth whether Wireless Local Area Networks (WLAN) a...

Abstract This paper presents a reflectarray antenna with an innovative dielectric mirror in the form of a discretized concave reflector. The mirror, manufactured via 3D printing, combines dielectric and air layers, formi...