Banca de DEFESA: LUIS FELIPE DE VASCONCELOS TORRES DA COSTA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : LUIS FELIPE DE VASCONCELOS TORRES DA COSTA
DATA : 13/07/2018
HORA: 09:00
LOCAL: Auditório do DCO, no CTEC
TÍTULO:

ANALYSIS OF CPW AND CPS ANTENNAS AND FSS WITH FRACTAL GEOMETRIES FOR WIRELESS COMMUNICATIONS SYSTEMS

PALAVRAS-CHAVES:

CPW antenna, CPS antenna, fractal antennas, compact antennas, wireless communications, FSS, frequency selective surfaces

PÁGINAS: 40
GRANDE ÁREA: Engenharias
ÁREA: Engenharia Elétrica
SUBÁREA: Telecomunicações
ESPECIALIDADE: Teoria Eletromagnetica, Microondas, Propagação de Ondas, Antenas
RESUMO:

The recent advance of technology on wireless communication systems has increasingly enabled the user to handle different applications. This has attracted great interest among microwave researchers, who work in mobile communications, short-haul links, wireless local area networks (WLAN) and satellite communications, for example. As a result, many researchers around the world are increasingly seeking to improve this technology to develop light, compact and inexpensive devices and equipments to operate in multiple communication services.

In this context, the development of planar microwave antennas and frequency selective surfaces (FSS) appears as an attractive alternative, due to their intrinsic properties such as small volume, reduced weight, low cost and ease of manufacture, besides allowing operating with different characteristics of radiation and polarization. Usually, planar microwave antennas are developed in microstrip lines and exhibit narrow bandwidth, being designed to operate in particular frequency ranges.

Recently, there has been a growing interest in the development of planar antennas in other planar transmission lines, among which are the coplanar waveguide (CPW) and the coplanar striplines (CPS). CPW antennas have larger bandwidths than microstrip antennas, and are suitable for the development of broadband antennas. CPS antennas can be used in both microwaves and millimeter waves.

In addition, there are also many studies being carried out on the development of selective frequency surfaces (FSS), as they act as spatial filters with compact, light, and low cost structures, which allow the transmission or rejection of microwave signals for designed frequency bands.

On the other hand, the fractal geometries, when used in planar antenna designs, allow the reduction of size and show the multiband behavior. In comparison with conventional planar antennas, the antennas with fractal geometries present lower resonance frequencies, allowing the manufacture of more compact antennas.

The main objective of this work is the simulation of CPW and CPS structures for the design of new CPW and CPS antennas with fractal elements for operation in the 1 GHz to 14 GHz band, aiming at applications in multiband, wide band and ultra wideband (UWB). In addition, the characteristics of radiation, gain and polarization of the antennas are observed. Computational simulations are performed and several configurations of CPW and CPS antennas and FSS are designed using Ansoft HFSS software. For purpose of comparison with the simulated results, several prototypes of CPW and CPS antennas are manufactured and measured. FSS structures are also designed, simulated and measured. The experimental results show a good agreement with the results of the numerical simulations performed for both antennas and HSS.

MEMBROS DA BANCA:
Presidente - 6345784 - ADAILDO GOMES D ASSUNCAO
Interno - 349732 - LAERCIO MARTINS DE MENDONCA
Externo à Instituição - ADAILDO GOMES D ASSUNCAO JUNIOR - IFPB
Externo à Instituição - JOABSON NOGUEIRA DE CARVALHO - IFPB