Accurate Permittivity Measurement Using the Cavity Perturbation Technique at ISM 5.8GHz Radio Band

In this paper, a new calibration method with two-filling factors for the permittivity measurement is proposed. With this calibration method, it is not necessary to measure the volume of the small sample, which not only eliminates the measurement error of the sample volume, but also simplifies the measurement procedure. To improve the measurement accuracy, the Cursor method, the resonance curve area (RCA) method and the Lorentzian fit method are utilized to process the measured resonant curve data so as to obtain accurate resonant frequency and quality factor. Finally, the obtained permittivity measurement results of a liquid sample validate the accuracy of this permittivity measurement approach.