Composition-engineered Sr_1-xBa_xTiO₃ for high-efficiency dielectric resonator antennas in 5G/6G bands

We report Sr_1-xBa_xTiO₃ (x = 0.0-0.4) nanoparticles synthesized by a tartrate-precursor combustion route and evaluate them for sub-6 GHz dielectric resonator antennas (DRAs). Structural (XRD, FTIR), microstructural (SEM/TEM), ferroelectric (P-E), thermal-conductivity, and broadband microwave-dielectric (1-15 GHz) characterizations identify x = 0.1 as the composition with the best balance of moderate effective permittivity, low loss, and stable GHz dispersion. A cylindrical DRA is then designed with Sr_0.9Ba_0.1TiO₃ as the matching layer between a Rogers 6010 resonator and a Rogers 4003 feed/ground laminate, and benchmarked against identical-geometry FR-4 and Rogers TMM4 matching layers. Simulated and measured S-parameters confirm efficient impedance matching (|S₁₁|_min ≈ - 25 dB; VSWR < 2), high realized gain, and stable radiation across 2.25-3.25 GHz, demonstrating that composition-engineered SBTO is a practical option for 5G/early-6G front-ends.