Understanding of the correlation of structural and microwave dielectric performance of (1-x)MgTiO3 - xCaTiO3 ceramics for dielectric resonator antenna applications

Abstract

In this article, the effect of CaTiO3 on the structural and microwave dielectric characteristics of MgTiO3 has been discussed. The (1-x)MgTiO3 - xCaTiO3 (abbreviated as (1-x)MT- xCT) for x = 0.025, 0.05, 0.075, 0.1 ceramics have been developed using a solid-state reaction route. The structural as well as morphological characteristics of specimens have been observed by employing X-ray diffraction and scanning electron microscope methods. The Rietveld refinement technique of X-ray diffraction data have been conducted for the refinement of structural phases. It suggests that two crystallographic phases have been present in all materials. The SEM images display dense well-identified grains of (1-x)MT - xCT (for x = 0.025–0.1) ceramics. The Raman spectroscopy method has been employed to detect the symmetry of ceramics and modes of vibration of the materials. The microwave dielectric characteristics like dielectric permittivity (εr), loss (tanδ), quality factor (Q×f), and temperature coefficient at resonant frequency (τf) of (1-x)MT - xCT (for x = 0.025–0.1) ceramics have been thoroughly investigated. The bond strength, bond valency, bond energy, and tolerance factor of (1-x)MT - xCT (for x = 0.025–0.1) materials have been evaluated and their relation with microwave dielectric characteristics has been discussed. The (1-x)MT - xCT (for x = 0.025–0.1) ceramics show excellent dielectric properties with near to zero τf. In addition, DRAs have been designed with (1-x)MT - xCT (for x = 0.025–0.1) materials as dielectric resonators and various antenna properties have been studied with the help of HFSS software. This work suggests that (1-x)MT - xCT for (x=0.05) material can be a promising candidate for DRA applications working in the C band.