FDTD Numerical Calculation of Shielding Effectiveness of Electromagnetic Shielding Fabric Based on Warp and Weft Weave Points

In this article, the finite-difference time-domain (FDTD) method is used to study the scientific numerical calculation method of the shielding effectiveness (SE) of the electromagnetic shielding (EMS) fabrics. First, the fabric is divided into overlapping region, longitudinal single yarn region, transverse single yarn region, and interstice region of the warp (weft) weave points according to the yarn arrangement characteristics of the warp and weft weave points. Then, a structure model of the fabric is established based on the warp and weft weave points and the fabric weave. The partition coefficient and discrete method of Yee's grid is determined. The electromagnetic parameters of the grid are measured by the coaxial transmission/reflection method, and the appropriate absorption boundary conditions, excitation sources, and constraints are set to establish the physical model of the fabric. Finally, the physical model is numerically calculated to obtain the SE using EastFDTD electromagnetic calculation software. The contrastive analysis of the numerical simulation and the measured data is made combining the theory. The accuracy of the numerical simulation results, the correction method of the discrete factor, and the reason of the error are discussed. It is concluded that the model has been satisfied with the numerical calculation of the SE of the EMS fabric.