Banca de DEFESA: BETOVEN OLIVEIRA DE ANDRADE

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : BETOVEN OLIVEIRA DE ANDRADE
DATA : 26/07/2019
HORA: 15:00
LOCAL: Auditório do Complexo Tecnológico de Engenharia - Campus Central - UFRN
TÍTULO:

Analysis and Design of Microstrip Patch Antennas  with substrate PBG printed 3D

PALAVRAS-CHAVES:

 Fractal Antenna, PBG Substrate, Artificial Neural Network, Wireless Communication, 3D Printing.

PÁGINAS: 94
GRANDE ÁREA: Engenharias
ÁREA: Engenharia Elétrica
SUBÁREA: Telecomunicações
ESPECIALIDADE: Teoria Eletromagnetica, Microondas, Propagação de Ondas, Antenas
RESUMO:

After a few decades of the first publications on microstrip antennas, research continues to expand. This is the consequence of several of its attractive features, especially the possibility of mounting in the same plane of the transceiver circuits. However, this advantage presents some problems - the waves produced by the circuits reflect and refract inside the substrate, since it has different refractive indices, which causes surface currents in the earth plane, leading to a narrow bandwidth and also to lower radiation efficiency and low gain, since some of the energy is wasted. In order to attenuate such negative characteristics, several techniques have been investigated and employed, one of the most promising being the use of PBG (Photonic Band Gap) substrates. PBGs are periodic structures in a dielectric or conductive material. They propagate the electromagnetic waves at a frequency specific to all states of polarization and angles of incidence. In this thesis, it is proposed an adequate methodology to study new structures and techniques aimed at the use of PBG material in the form of three-dimensional periodic (3D) holes in the substrate in the manufacture of microstrip patch antennas for the range between 1 to 4 GHz. This thesis presents some contributions, as described below: (i) proposition of new antennas, including antennas with printed substrates (3D); (ii) theoretical development of coherent antenna design, avoiding resonance frequency shifts, caused by changes in the permittivity after insertion of the holes; (iii) demonstration that different hole geometries are not related to resonance frequency variation; (iv) analysis that an unconventional geometry can promote large efficiency improvements in computational design time; (v) applying an artificial neural network capable of substantially improving the time to obtain the return losses; (vi) proposition of low-cost techniques for the development of antennas with PBG substrate. In order to validate the proposed antennas, simulations and measurements are presented and discussed.

MEMBROS DA BANCA:
Presidente - 349732 - LAERCIO MARTINS DE MENDONCA
Interno - 6345784 - ADAILDO GOMES D ASSUNCAO
Interno - 2524053 - ANTONIO LUIZ PEREIRA DE SIQUEIRA CAMPOS
Interno - 1422265 - JOSE PATROCINIO DA SILVA
Externo à Instituição - HUMBERTO DIONISIO DE ANDRADE - UFERSA
Externo à Instituição - WELLINGTON CANDEIA DE ARAUJO - UEPB