Fabrication of High Radiation Efficiency Dielectric Resonator Antenna Array Using Temperature Stable 0.8Zn₂SiO₄-0.2TiO₂ Microwave Dielectric Ceramic

Array antenna is of great significance in realizing the Sub-6 GHz fifth-generation (5G) mobile communication systems, however, its utilization in the base station systems implementation is limited due to high power consumption. In this paper, a high radiation efficiency 4 × 4 cylindrical dielectric resonator antenna (CDRA) array fabricated using the temperature stable 0.8Zn₂SiO₄-0.2TiO₂ composite ceramic is proposed. TiO₂-doped Zn₂SiO₄ composite ceramics are synthesized by the conventional solid-state method. Notably, 0.8Zn₂SiO₄-0.2TiO₂ composite ceramic sintered at 1250 °C demonstrates excellent microwave dielectric properties with dielectric constant (ε_r ≈ 8.24), high-quality factor (Q × f ≈ 35 000@8.08GHz), and the temperature coefficient of resonant frequency (TCF ≈ +4.6 ppm °C⁻¹). Moreover, the composite ceramic CDRA array is designed by exciting fundamental HE_11δ mode using the aperture coupling microstrip feeding network. The fabricated composite ceramic based 4 × 4 CDRA array has enhanced measured radiation efficiency of up to 87%, high gain of 17.85 dBi and is a promising candidate for utilization in Sub-6 GHz 5G Base Station communications systems.