Thickness-Invariant Complex Permittivity Retrieval from Calibration-Independent Measurements

A calibration-independent method is proposed for accurate complex permittivity (epsilon(r)) determination of dielectric samples from raw scattering parameter measurements without resorting to any information of thickness (L), especially for thinner samples. X-band waveguide measurements of two polyethylene samples were carried out for validation of our method. From our analysis, we note that while our method extracts similar epsilon(r) for both samples (thickness-invariant), accuracy of tested methods greatly degrades by an inaccurate knowledge of L.