Dynamic measurement of complex permittivity in microwave material using microwave power

A cavity resonator and microwave heating system has been designed to measure the temperature dependent complex permittivity of dielectric materials in microwave frequency. To measure the temperature dependent complex permittivity of material, the output power of vector network analyzer is amplified to heat materials and obtaining complex permittivity by measuring transmission coefficient of cylindrical cavity resonator. From the results, it is found that the temperature dependent complex permittivity is obtained by perturbation and rigorous methods in wide temperature range with microwave heating dynamically.