MgTiO3–CaTiO3 Microwave Dielectric Ceramics for High-Performance Dielectric Resonator Antenna by Optimized Epoxy Gel Casting

MgTiO3–CaTiO3 ceramics have been widely used in 5G antenna systems. In this study, the MgTiO3–CaTiO3 ceramics were fabricated by epoxy gel casting and compared with dry pressing. The effects of slurry rheological properties and sintering temperature on the microstructure and microwave dielectric properties of ceramics were studied. It was found that epoxy gel casting could significantly increase the Q × f value. The Q × f value of the epoxy gel casting reached 63 377 GHz, representing a 17.3% increase compared to the dry pressing value of 54 000 GHz. Additionally, the sintering temperature was reduced by 25 °C. Furthermore, the high Q × f value of the EGDGE–PEI gel casting optimized MgTiO3–CaTiO3 ceramics suggests great potential for use in 5G antenna systems. The MgTiO3–CaTiO3 dielectric resonator antenna was designed and fabricated, and it exhibited a resonance frequency of 4.18 GHz with a bandwidth of approximately 100 MHz. The simulated gain and efficiency were found to be 6.46 dBi and 96.2%, respectively.