Calibration-Independent and Position-Insensitive Transmission/Reflection Method for Permittivity Measurement With One Sample in Coaxial Line

In recent decades, the calibration-independent methods have successfully been employed to determine the complex permittivity of dielectric materials without the need of calibration before measurements. However, these methods experience their respective problems from the requirement of two samples, the movement of the sample, or the introduction of extra assistant transmission lines. To eliminate these problems, a simple method is proposed based on transmission/reflection method in this paper. This method can afford high accurate measurement results without singularities by only two measurements of uncalibrated scattering parameters with one sample and one line. One measurement is for the empty fixture and the other for the same fixture holding the sample at a single position. Additionally, the principle of the proposed method ensures it independent of the fixture and the sample position. Some experiments were made using the vector network analyzer 8753ES and a Φ 16-mm coaxial line fixture. The proposed method is validated by the measurements of the permittivity of polytetrafluoro ethylene from 2 to 6 GHz.