Microwave characterisation of BaCe_2Ti_5O_15 and BaNbO_15 ceramic dielectric resonators using whispering gallery mode method

摘要

A microwave dielectric ceramic resonators based on BaCe_2Ti_5O_15 and Ba_5NbO_15 have been prepared by conventional solid state ceramic route. The dielectric resonators (DRs) have high dielectric constant 32 and 40 for BaCe_2Ti_5O_15 and Ba_5Nb_4O_15, respectively. The whispering gallery mode (WGM) technique was employed for the accurate determination of The dielectric properties in the microwave frequency range. The BaCe_2TiO_15 and Ba_5Nb_4O_15 have quality factors (Q×F) Of 30, 600 and 53, 000 respectively. The quality factor is found to depend on the azimuthal mode numbers. The temperature Coefficient of resonant frequency (T_f) fo BaCe_2Ti_5O_15 and Ba_5Nb_4O_15 have been measured accurately using different Resonant modes and are +41 and +78 ppm/K, respectively.