A Self-Gap-Correction Method for Broadband Measurement of Complex Permittivity

A novel self-gap-correction method for accurately measuring the broadband permittivity of materials based on the transmission/reflection theory is proposed. A combination strategy of the electromagnetic finite element simulation (FEM) and a hybrid optimization algorithm is employed to rapidly extract the true values of the gap size and permittivity. This method relaxes the fully filled assumption of the test specimens and realizes the self-correction of air-gap effect without requiring its exact size. The high accuracy and practical suitability of the proposed method are validated through experimental tests.