Optimization of Microwave Dielectric Properties of (100‐X)BaBi₄Ti₄O₁₅ – (X)Nb₂O₅ Composites for Microwave

This study focuses on experimental investigations and numerical simulations of microwave dielectric properties and dielectric resonator antenna behavior based on the BaBi 4 Ti 4 O 15 ceramic matrix. BaBi 4 Ti 4 O 15 is doped with niobium oxide (Nb 2 O 5 ) in proportions of 2, 5, and 10%. The ceramic is obtained through the solid‐state reaction method. The resulting structures and dielectric properties of the samples are analyzed using powder X‐ray diffraction, Raman spectroscopy, and scanning electron microscopy to examine the crystalline phases present in the ceramics. The Hakki–Coleman method is used to clarify the properties of permittivity and dielectric loss. The temperature coefficients of the resonant frequency ( τ f ) range from –396.95 to –181.44 ppm °C −1 . Experimental measurements of the dielectric resonators, serving as antennas, yielded results such as reflection coefficient, gain, efficiency, bandwidth, and input impedance. The simulations aligned well with experimental results, suggesting the potential application of this material as an antenna device in the microwave spectrum.