BROADBAND COMPLEX PERMITTIVITY MEASUREMENT OF LOW LOSS MATERIALS OVER LARGE TEMPERATURE RANGES BY STRIPLINE RESONATOR CAVITY USING SEGMENTATION CALCULATION METHOD

A system has been developed for measuring the complex permittivity of low loss materials at frequencies from 500 MHz to 7 GHz and over a temperature range up to 1500 degrees C using stripline resonator cavity method. Details of the design and fabrication of the cavity were discussed. Particular features related to high-temperature operation were described. An improved resonance method at high temperature for determining complex dielectric properties of low-loss materials was developed. The calculation process was given by a physical model of the stripline resonator cavity at high temperature. The paper brought forward the method of segmentation calculation according to the temperature changes over the cavity, which matched the actual situation of high temperature measurements. We have verified the proposed method from measurements of some typical samples with the available reference data in the literature.