High thermal stability OF Li2TiO3-Al2O3 composite in the microwave C-Band

In this study, we analyzed composites based on Li2TiO3-Al2O3 in the microwave range by measuring their dielectric properties comprising the temperature coefficient of the resonant frequency (τf), relative dielectric permittivity (εr), and dielectric loss (tanδ) in the C band (4-8 GHz). The Li2TiO3 phase was obtained by solid-state reaction and the ceramic composites were obtained by blending phase 2 with 5, 10, 15 and 20 wt% of Al2O3. We then analyzed these ceramic composites as dielectric resonator antenna. The results showed that the alumina addition of 5 wt% improved the τf value for the composites (τf = −0.58 ppm °C−1) but the other dielectric properties did not improve with the alumina concentration, where the permittivity decreased and the dielectric loss increased. According to the antenna measurements, all of the samples exhibited good performance in terms of the gain (3.91-5.67 dBi), bandwidth (338-500 MHz), and efficiency (70.58-96.84%) compared with previous findings.