Measurement of Complex Permittivity of Materials Using Electromagnetic Wave Propagation in Free Space and Super High-Resolution Algorithm

摘要

In this paper, we propose a model that can be used to estimate the complex permittivity of a material sample placed in free space using a super high-resolution algorithm. The measurement system consists of a transmitting and a receiving horn antennas, a network analyzer, and a computer. Operating in 8.0-12.0 GHz frequency range, it could be used to measure the transmission coefficient (S₁₂ or S₂₁) through the material sample. From the measured values of S₁₂ or S₂₁, the complex permittivity of the material is estimated by multiple signal classification (MUSIC) algorithm. The proposed method is verified for POM-C sample with different numbers of frequencies. The results show that the dielectric constant of POM-C sample is determined accurately when the number of frequencies is more than or equal to 201 in the frequency range of 8.0 GHz to 12.0 GHz.