Rapid Calculation Method of Ultrathin Dielectric Layer Shielding Efficiency Based on CNTD-FDTD Method

In many practical applications, it is essential for modeling the propagation of electromagnetic energy through thin lossy material layers such as those found in automotive and electronic equipment enclosures Many existing schemes suffer problems of late time instability and large computational costs. Therefore, a new method of modeling thin lossy materials in finite difference time domain (FDTD) format is studied in this paper. For this, the thin layer material is spatially discretization by using one-dimensional sub grid. At the same time, in order to overcome the additional time step limitation caused by the reduction of spatial element size, the Crank Nicolson time-domian (CNTD) integration scheme is used in the subgridded zone, and the hybrid explicit implicit method is combined with the one-dimensional time-domain finite difference method used outside the thin layer. The experimental results show that this method overcomes the instability problem of thin layer loss materials at a lower computational cost, and its accuracy is demonstrated by numerical experiments applied to the shielding efficiency of heterogeneous dielectric layers.