Fabrication of Wideband Low‐Profile Dielectric Patch Antennas from Temperature Stable 0.65 CaTiO ₃ –0.35 LaAlO ₃ Microwave Dielectric Ceramic

In this paper, the medium dielectric constant 0.65CaTiO3-0.35LaAlO3 (CTLA) composite microwave ceramic is employed to introduce in dielectric patch antennas (DPA). Typical, high-performance microwave dielectric properties of εr ≈ 44.8, Q × f ≈ 43 950 GHz@3.67 GHz and TCF ≈ 0 ppm °C–1 can be obtained by solid-state reaction method in CTLA composite microwave ceramics sintered at 1450 °C for 2 h. Then, the CTLA composite ceramic patch fired with silver coating is mounted on the Rogers RO4003C substrate operating as a magnetic wall boundary. A simplified cavity-like theoretical model is used to analyze the proposed DPA structure and the accuracy of this antenna model is evaluated by the theoretical results from a commercial CST Microwave Studio 2019. Based on this, the CTLA composite ceramic physical property is modified to enhance the radiation efficiency and reduce profile of the DPA. The higher-order TM121 mode is brought close to the dominant TM101 mode by taking advantage of the multimode characteristics of the dielectric patch resonator and introducing a sintered silver slot in the ceramic dielectric patch. For demonstration, the proposed DPA prototype operating in the multiprobe antenna near the field measurement system is implemented and measured.