This study analyses the effects caused by a new hexagonal defect ground‐plane (DGS) structure when it is applied to a rectangular microstrip antenna and studies its effectiveness to suppress higher‐order modes. To improve the rejection characteristics of the analysed DGS, a genetic algorithm was used to optimise its parameters. Controlling higher‐order modes of the fundamental operating frequency was successfully demonstrated, and the experimental results showed that optimising the hexagonal DGS could enhance the S11 parameter of the fundamental mode while simultaneously suppressing or further attenuating higher‐order modes. Such results are particularly important once DGS is applied for self‐immunity of antennas against harmonic radiations by avoiding the use of a filter circuit.

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In this article, a new project of a rectangular microstrip patch antenna, operating at 5.8 GHz, optimized by Genetic Algorithm (GA), has been proposed, built and analyzed. That antenna has a structure composed by inset‐fed, which is made in the junction between the patch and the feed line. The proposed GA is applied to determine the depth (yo) of the insert‐fed, which refers to how much the feed line get in the patch in order to achieve the optimum value for the impedance matching of the antenna. Obtained results for the optimized antenna were compared to those achieved by simulation and measurements of a reference antenna, also two prototypes were built for both one. In this study, the analyzed parameters were total gain, S11 parameter, input impedance and E‐plane. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:105–109, 2017

Este artigo tem por objetivo destacar a importância do desenvolvimento de jogos digitais para o processo de ensino e aprendizagem da Matemática. Os jogos digitais foram desenvolvidos utilizando conceitos de gamificação e a engine Unity 3D. Quatro jogos com temática educacional da Matemática foram desenvolvidos por alunos da 3ª série de Informática do IFAM Campus Tefé, o que trouxe novas oportunidades para uma área que encontra-se em crescimento.