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Nowadays, optical amplifiers designs are induced by new requirements generated by optical networks. The introduction of WDM reconfigurable networks with increasing rate from 10-40 Gb/s to 100 Gb/s and beyond, demand new ...

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 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...

Abstract A GPU-adapted Finite Element Method (A-FEM) implementation without using a mesh coloring strategy to avoid race conditions is presented. All the elements are simultaneously processed, and the local data is compu...

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...

In this paper, we present a comparison between OFDM and STDCC sounding techniques used to wide band channel characterization in suburban environments at 3.5 GHz band. Measurements of the received signal's power delay pro...

Abstract This work presents four systems for generation of optical subcarriers in the C-band in optical communications, based on serial and parallel amplified optical ring resonator with phase modulation and 10 GHz spect...

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...

Fiber-To-The-Home (FTTH) technology has been significantly implemented in access networks, providing very high data rates transmission and a variety of digital content to subscribers. It involves an optical cable link be...

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 ...

Abstract The single phase equivalent circuit is largely used to model the three-phase induction motors in steady-state operation and under sinusoidal balanced voltages. Depending on the desired application, the circuit m...

Abstract This article discusses procedures for production of tapered fibers in different diameters (tapers) and Bragg gratings writing (tFBG) in such fibers. The reflection spectra in different tFBGs are compared with a ...

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...

Abstract This article describes the use of a low-cost softwaredefined radio applied to an Electromagnetic Compatibility (EMC) test. The proposed system is indicated for cases when an autonomous instrument is better suite...

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 Radio-Frequency Identification (RFID) is one of the leading enabling technologies of the Internet of Things (IoT) at low cost and high granularity scenarios. The cost of implementing IoT applications concerns th...

Abstract Optical plasmonic nanoantennas have proven useful in nanoplasmonic applications, paving the way for more efficient wireless optical communications. In this work, we propose a parametric study of a plasmonic horn...

Abstract High-Definition Digital Terrestrial Television (HDDTT) replaces analogue, requiring further research on propagation links due to atmospheric variables potentially disrupting signals during uplink and downlink re...

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— A coplanar waveguide (CPW)-fed patch antenna with triple wideband is presented for simultaneously satisfying Wireless Local Area Network (WLAN) and Worldwide Interoperability for Microwave Access (WiMAX) appl...

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...

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 Irregular terrains covered with forest vegetation represent a challenging scenario for radio planning. A case of particular interest is the one where a forest-covered high hill or mountain is interposed to the l...

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...