Estudo das propriedades dielétricas e elétricas das matrizes Mg4Nb2O9 para aplicações em componentes de rádio frequência e microondas

• Main Author: Silva Filho, José Miranda da
• Publication Date: 2017
• Format: Doctoral thesis
• Language: por
• Source: Repositório Institucional da Universidade Federal do Ceará (UFC)
• Download full: http://www.repositorio.ufc.br/handle/riufc/29451
• topic: Teleinformática; Espectroscopia de impedância; Impedância dielétrica; Cerâmicas dielétricas; Microondas; Dielectric resonator antennas; Impedance spectroscopy; Microwave frequency

The electrical and dielectric properties of microwave ceramics Mg 4 Nb 2 O 9 were studi ed and analyzed to improve its main constituent parameters: relative permittivity ( r  ), quality factor ( Q ) and temperature coefficient of resonance ( f  ) for implementation in micro wave and radio frequency devices. In order to achieve best values of electrical and dielectric properties, V 2 O 5 additions in different percentages were carried out for a qualitative and quantitative comparison through analysis of complex impedance spectros copy. The preparation and fabrication of resonator dielectric antennas (DRAs ) using the samples with the best electrical and dielectric properties was also accomplished . The parameters of the (DRAs) were then used to solve the electromagnetic fields and ge nerate scattering parameters to better predict performance of devices in a microwave and radio frequency range using HFSS simulator software based on the finite elements method.