Permittivity Measurement Using the Normalized Euclidean Distance Based on Dispersion of Spoof Surface Plasmon Polaritons

A new permittivity measuring method combining with the normalized Euclidean distance (NED) based on the dispersion property of spoof surface plasmon polaritons (SSPPs) is proposed in this paper. Based on this method, a sensor is proposed and the SSPP transmission line which is easily influenced by permittivity variation of surrounding environment constitutes the key part to the sensor. The transmission line is placed along the edge of the board for non-destructive detection. Due to the dispersion property of SSPP structure, the time domain pulse distortion would change with permittivity variation. A monotonic mapping relationship is obtained between NED and the permittivity of materials under test (MUT). Therefore, permittivity could be obtained by measuring the NED. The simulated processes of calibration and measurement results show high accuracy level (typical error is 0.29
^%
) of this method and it could be utilized in short pulse applications.