Temperature-stable low-loss medium-dielectric microwave dielectric ceramic and preparation method thereof

The invention provides temperature-stable low-loss medium-dielectric microwave dielectric ceramic and a preparation method thereof, and solves the problems of low quality factor and large temperature coefficient of resonance frequency of medium-high dielectric microwave dielectric ceramic. The temperature-stable low-loss medium-dielectric microwave dielectric ceramic is synthesized by taking Ca0.8Sr0.2TiO3 ceramic as a matrix and SmAlO3 as a doping agent; the temperature-stable low-loss medium-dielectric microwave dielectric ceramic presents a single orthorhombic phase, the chemical formula of the temperature-stable low-loss medium-dielectric microwave dielectric ceramic is Ca0.52Sr0.13Sm0.35Ti0.65Al0.35O3, the dielectric constant of the temperature-stable low-loss medium-dielectric microwave dielectric ceramic is 35.7-42.0, the quality factor of the temperature-stable low-loss medium microwave dielectric ceramic is 22770-39120 GHz, and the temperature coefficient of resonance frequency is -11.5 ppm/DEG C to