A Study on the Correction of Reflection and Transmission Coefficients for Electromagnetic Waves Incident on Dielectric and Plasma Based on FDTD Method

This paper proposes a method based on Finite-Difference Time-Domain (FDTD) to calibrate the reflection and transmission coefficients from the antenna transceiver ports to the interface of the measured medium. During testing, the reflection and transmission coefficients at the medium interface are automatically calibrated through testing and the built-in program of the vector network analyzer (VNA), which is not conducive to the rapid analysis of parameters. In this paper, the algorithmic calibration of reflection and transmission coefficients on dielectric and plasma was achieved by simulating electromagnetic wave incidences on ideal conductors and direct transmission using FDTD. Furthermore, in conjunction with the free-space method, we corrected the reflected and transmitted coefficients after calibration, and validated the accuracy of this correction approach through experiments. The calibration and correction method presented in this paper provide important guidance for precise measurements of medium parameters and high-precision diagnostics of plasma.