Evaluation of MnFe2O4-SiO2 composite dielectric resonator synthesized from in natura ores

Abstract

We present the evaluation of a ferrite resonator antenna designed from MnFe2O4-SiO2 composite. The composite was synthesized from in natura ores, extracted in the state of Rio Grande do Norte, by solid state reaction. Two pellets were manufactured using 370 MPa and 740 MPa. Dielectric characterizations were performed previously, and new results are presented. Pressure increment led to a growth in MnFe2O4 phase, from 88.7% to 90.1%, and a decrease in ferrite and cristobalite crystallite size. Dielectric constant presented well-defined behavior close to 5.0 and agreement with morphological characteristics. Ferrite resonator was simulated according to the dielectric characterizations and magnetic properties estimative. TM110 theoretical results are presented and compared with the presented resonator. Reflection coefficient measurements are presented and compared to simulations. The error achieved in resonance frequency was lower than 0.15%, simulated radiation patterns presented low cross-polarization, below −55.33 dB. Simulated directivity, gain and efficiency are presented and discussed.