An Efficient Numerical Technique to Predict Phase Responses of Reconfigurable Reflectarray Cells with Mutual Coupling

International audienceThis paper presents a numerical technique to predict realistic phase responses of active cells within a reflectarray. The phase responses of an active cell are determined as a function of the states of the neighboring cells. The phase probability distributions are computed and realistic phase responses are then evaluated. A synthesis application is presented in order to highlight the interest of the realistic phase responses

Global technique analysis for reconfigurable reflectarray antennas

International audienceThis paper focuses on the simulation of reconfigurable reflectarrays. A new method combining the 'surrounded-cell' approach and the compression method is presented. The method considers the real environment of the radiated elements and it only requires one lightweight electromagnetic simulation for the whole reflectarray

Experimental demonstration of metamaterials application for mitigating scan blindness in phased array antennas

This paper presents two metamaterial-inspired solutions to mitigate the scan blindness effects in a phased array antenna. In the first solution, portions of a bed of nails are introduced in the radome to prevent the excitation of surface waves. In the second solution, a superstrate metasurface is designed to synthesize a permittivity tensor optimized to achieve a wide angle impedance matching. In both approaches, the numerical simulations are successfully compared with measurements of a phased array antenna prototype with 100 elements. The wire medium-based solution reveals an effective way for reducing the blind-spot in a wide bandwidth, while the metaradome has been found less suitable for the same purpose.This work was supported by the METALESA project A-1089- RT-GC that was coordinated by the European Defence Agency (EDA) and funded by 11 contributing Members (Cyprus, France, Germany, Greece, Hungary, Italy, Norway, Poland, Slovakia, Slovenia and Spain) in the framework of the Joint Investment Programme on Innovative Concepts and Emerging Technologies (JIP-ICET)

A simple and fast technique to analyze accurately reconfigurable reflectarrays

International audienceA simple and fast technique is proposed and validated to analyze reconfigurable reflectarrays. This technique takes into account mutual coupling effects between active cells within the array. Its novelty relies on the ease of use, the accuracy and the promptness for analyzing reconfigurable reflectarrays

Technique d'analyse globale pour antennes réseaux réflecteurs reconfigurables

National audienceCet article se focalise sur la simulation de reflectarrays reconfigurables. Une nouvelle technique d'analyse combinant l'approche de la cellule environnée et la méthode de compression est présentée. Elle considère l'environnement réel des éléments rayonnants et ne nécessite qu'une seule simulation électromagnétique suivie de simulations circuits pour l'ensemble du reflectarray

Research Article An Efficient Resource Management Protocol for Handling Small Resource in Wireless Sensor Networks

Copyright © 2013 Wan-Hee Cho et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Wireless sensor nodeswith single chipsmay have insufficient resources for certain applications.We propose a resourcemanagement protocol for applications with constrained resources to improve effectiveness by borrowing resources from a resource management server. 1

A New Approach Combining Surrounded- Element and Compression Methods for Analyzing Reconfigurable Reflectarray Antennas

Abstract—An efficient technique to provide fast and accurate analysis of large-scale and complex reconfigurable reflectarray antennas is presented and validated. The method combines the surrounded cell approach and the compression technique to analyze the global array. It takes into account the mutual coupling effects and the numerical complexity is reduced. Only a minor electromagnetic simulation and a fast post-processing are required. Index Terms—Reconfigurable reflectarray, rigorous analysis, surrounded cell approach, compression technique. R I

Experimental Microwave Complex Conductivity Extraction of Vertically Aligned MWCNT Bundles for Microwave Subwavelength Antenna Design

International audienceThis paper reports the extraction of electrical impedance at microwave frequencies of vertically aligned multi-wall carbon nanotubes (VA MWCNT) bundles/forests grown on a silicon substrate. Dedicated resonating devices were designed for antenna application, operating around 10 GHz and benefiting from natural inductive/capacitive behavior or complex conductivity in the microwave domain. As obtained from S-parameters measurements, the capacitive and inductive behaviors of VA MWCNT bundles were deduced from device frequency resonance shift

Intégration d'un modèle électrothermique comportemental d'amplificateur de puissance RF sous l'environnement ouvert simulation système SCILAB/SCICOS

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