A measurement method for electromagnetic parameters of flexible materials in low frequency band

In this paper, a measurement method for electromagnetic parameters of flexible materials based on air coaxial line in low frequency band is proposed. First a material with known electromagnetic parameters and smooth surface is selected as the substrate, the flexible material is attached to the substrate and loaded into the air coaxial line together. Then calibration kits open and short are connected to the terminal of the air coaxial line respectively, and the single-port reflection coefficient of the device is measured by vector network analyzer (VNA). Finally, the electromagnetic parameters of the flexible material are deduced based on the impedance of the specimens section in air coaxial line. Experimental results show that the method proposed in this paper is effective and reliable.