volume | PIER Journals

Abstract

The closed cavity method is proposed to measure the frequency temperature coefficient (τ_f) of a dielectric resonator. The τ_f polynomial, which is linear combination of the temperature coefficient of relative dielectric constant and the linear expansion coefficient of the dielectric and cavity, is given. The coefficients of τ_f polynomial are discussed in detail. The intrinsic temperature coefficient of resonant frequency (τ_f0) is introduced to improve the measurement precision. Resonators made of BaO-TiO₂-Sm₂O₃ and (Zr_0.8Ti_0.2)TiO₄ ceramics with Teflon and alumina as supports were measured. The results show that the τ_f values of the same resonator with above supports are different, and the measured variation between them is more than 3 ppm/˚C. Using the concept of τ_f0, the variation is less than 2 ppm/˚C.

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Professor Liangzu Cao

Dr. Jun-Mei Yan

Dr. Lixia Yin