Dynamic measurement of temperature dependent permittivity and permeability by microwave irradiation

To measure the temperature dependent complex permittivity and permeability of materials, measuring systems using cavity resonator in the frequency band of 2.45 GHz have been developed. To measure low loss material with wide temperature range, TE103 mode cavity resonator system excited by magnetron as power source has been applied. To measure higher loss material with high accuracy, TM010 mode cavity resonator system excited by solid state power source with vector network analyzer has been applied. By measuring transmission or reflection coefficient of the cavity with measuring the temperature using infrared thermograph, the temperature depending complex permittivity and permeability can be obtained. By using the developed systems, temperature dependent permittivity and permeability for metallic powders and ceramics have been measured and the results are shown in this paper.