A test system for complex permittivity measurements of low-loss materials at high temperatures up to 2000 °C

Abstract

A microwave test system to measure the complex permittivity of a low-loss material as a function of temperature has been developed, and it is based on the short-circuited line method. The calibration method for the microwave loss and the phase of the waveguide holder which vary with temperature is discussed in detail. Induction heating is employed to shorten the heating and cooling time of the sample and waveguide. The test system was built at 10 GHz and over the temperature range from room temperature to 2000 °C. The feasibility of the system has been verified by measuring the complex permittivity of quartz at high temperatures.