Numerical calculation of shielding effectiveness of electromagnetic shielding fabric based on finite difference time domain

Numerical calculation of shielding effectiveness (SE) of electromagnetic shielding fabric (EMSF) is a research difficulty and there is not an effective method to resolve the difficulty at present. The finite difference time domain (FDTD) method is used to study this issue in this paper. Firstly, this paper constructs a structure model based on the warp and weft densities and yarn diameter according to the structure feature of the EMSF. Secondly, a physical model of the EMSF is built by determining the partition coefficient, the Yee's mesh discretization method, and the absorption boundary which are suitable for the structure model. Then the excitation parameters are set using the EastFDTD electromagnetic computing software and the SE is obtained by the numerical calculation for the physical model. Finally, a number of silver fiber EMSFs and stainless steel fiber EMSFs with different fabric weaves, densities and metal contents are tested to verify the proposed model. The calculation data are compared with actual test data. By analyzing the differences and influencing factors between the two data, we concluded that the proposed model can calculate the SE of the EMSF and the results were satisfied. This paper provides a new method for the numerical calculation of the SE of the EMSF, and possesses an important reference value for the SE forecast, shielding mechanism analysis, shielding rules researches and related shielding electromagnetic computation of the EMSF.