Navegando por Assunto "Antenas de grafeno"

Agora exibindo 1 - 3 de 3

Acesso aberto (Open Access)
Antena de grafeno composta de dipolo-espira para aumento da largura de banda
(Universidade Federal do Pará, 2017-02-17) AZEVEDO, Rodrigo Guimarães de; COSTA, Karlo Queiroz da; http://lattes.cnpq.br/7932708321834647
This work presents a graphene antenna composed by a planar dipole and a circular loop for increasing bandwidth in the terahertz range. The dipole is fed by a voltage source in its gap and the circular loop is a parasitic antenna without physical connection with dipole. The two-dimensional method of moments (MoM-2D) with surface impedance is used for numerical analysis of this antenna compound antenna. It is investigated the influence of geometry and the chemical potential of loop element on the input impedance and bandwidth of the dipole element, with objective to obtain broadband operation.
Acesso aberto (Open Access)
Antenas de grafeno com controle de diagrama de radiação: projeto e modelagem via método FDTD
(Universidade Federal do Pará, 2015-08-28) RODRIGUES, Nilton Rodolfo Nascimento Melo; DMITRIEV, Victor Alexandrovich; http://lattes.cnpq.br/0684541646225359; OLIVEIRA, Rodrigo Melo e Silva de; http://lattes.cnpq.br/4768904697900863
In this work, it is developed a mathematical formulation for modelling Graphene sheets in the three-dimensional lattice used to solve Maxwell’s equations with Yee’s algorithm. The technique is based on piecewise linear recursive convolution method and on thin material sheets technique, valid in intraband range. The HFSS software is used for to designing, for the first time, graphene antennas with dynamic control of the radiation pattern main lobe by tuning the chemical potential of graphene sheets used as passive elements. The numerical method developed in this work fully agrees with the results obtained by using HFSS (this one is based on the Finite Element Method).
Acesso aberto (Open Access)
Controle do diagrama de radiação de dipolo de grafeno pelo potencial químico
(Universidade Federal do Pará, 2018-12-13) PINTO, Gabriel Silva; COSTA, Karlo Queiroz da; http://lattes.cnpq.br/7932708321834647
This work presents a method of controlling the radiation diagram of a graphene dipole by the chemical potential. The dipole analyzed has rectangular geometry with power supply by voltage source in the center, where each arm of the dipole is maintained to a different chemical potential. The geometry is analyzed by the two-dimensional moments method (MoM-2D) in MATLABr software, with an equivalent surface impedance. Calculations of the main radiative properties of the antenna are presented as a function of the chemical potential. The results show that the greater the difference between the chemical potentials, the greater the displacement of the main lobe of the radiation diagram.