In this study, ceramics in the 0.90Na$_{0.5}$Bi$_{0.5-x}$La$_{x}$TiO$_{3}$--0.03NaNbO$_{3}$ --0.07 Ba(Zr$_{0.2}$ Ti$_{0.8}$)O$_{3}$ series (where $x = 0.00, 0.03,$ $ 0.05, 0.07$) were processed via a solid-state reaction method. The phase, microstructural features, and dielectric properties, particularly the dielectric constant and dielectric loss, were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), and dielectric spectroscopic techniques, respectively. XRD analysis revealed a single perovskite phase, while SEM analysis showed a dense microstructure with reduced grain size as the $x$ content increased. The increase in doping content enhanced the relaxor characteri... More >