Banca de DEFESA: CRISLANE PRISCILA DO NASCIMENTO SILVA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : CRISLANE PRISCILA DO NASCIMENTO SILVA
DATE: 21/02/2022
TIME: 10:00
LOCAL: Sessão por Videoconferência
TITLE:

INTEFEROMETER AND MULTI-BAND SENSOR BASED ON THE HILBERT FRACTAL CURVE.

 

 

KEY WORDS:

Microwave devices. Hilbert fractal. Miniaturization. Frequency Measurement. Interferometer. Multiband sensor. Dielectric characterization.

PAGES: 82
BIG AREA: Engenharias
AREA: Engenharia Elétrica
SUMMARY:

Fractal geometry has been widely studied and applied in the design of microwave planar devices. Due to their properties of self-similarity and self-filling, they are applied in the design of filters, selective surfaces in frequencies, antennas, etc., mainly to obtain the miniaturization of their structures and improvement of their frequency responses. In this sense, this thesis project proposes to use Hilbert's fractal curve for miniaturization of two microwave devices. The first one is a reconfigurable planar interferometer in which the delay line is based on the second interaction of the Hilbert fractal curve. PIN diodes are used to switch between states or lines of delays. The reconfiguration of Hilbert's fractal curve, which has the property of self-filling space, allows the design of more compact interferometers. Simulation and experimental results are presented here for a 3-bit interferometer that operates between 2.7 to 4.5 GHz. The second device consists of a multi-band fractal sensor using the fourth iteration of the Hilbert fractal curve that is used to obtain a compact resonator. The design, simulation and measurement results are here presented and they are in good agreement. The sensor has five resonant frequencies: 0.59, 1.73, 2.84, 3.88 and 4.92 GHz. Calibration curves were raised with substrates with known permissiveness and they have shown a high linear degree. The results show that it is possible to use the sensor to characterize real permissiveness of substrates with low losses at five different frequencies.

 

BANKING MEMBERS:
Externo à Instituição - EVANDRO CONFORTI - UNICAMP
Externo à Instituição - ADAILDO GOMES D ASSUNCAO - UFRN
Externo à Instituição - IGNACIO LLAMAS GARRO
Externo à Instituição - JOAO CRISOSTOMO WEYL ALBUQUERQUE COSTA - UFPA
Presidente - 2131653 - MARCOS TAVARES DE MELO