The Study On Slot Coupling And Three-dimensional Subgridding Method

The Finite-Difference Time-Domain (FDTD) method has been effectively applied to analyse electromagnetic (EM) scattering problems. In the paper, the research of the object which has the partially fine parts is made by subgridding method. The partially fine parts are concerned by subgridding method and in the other region coarse grid method is applied. This method compared with uniform fine grid applied in the whole modeling region shows the computer memory is less and processing time is shorter, and what's more, it quite ensures precision of calculation.In this paper, first, the finite-difference time-domain Yee's method is introduced. The difference equations, the stability condition, numerical dispersion characteristic and absorbing boundary condition are discussed. Primary research is done into the position of incident plane wave, and analysis is made on the interpolation equations of incident plane wave in grid space when its parameter (θ,φ,α) is a particular value. The influence of incident plane wave parameter on coupling power of slot is also explored.In this paper, the three-dimensional subgridding method is mainly discussed. Finite-difference time-domain equation is deduced from Ampere and Faraday's laws. Subgridding method is introduced in order to calculate electromagnetic scattering around slots of the target with more precision and effectiveness. The paper introduces two theoretical analyses of three-dimensional subgridding methods, namely, wave equation subgridding method and subgridding method of traversing different materials. To the former method, we use the homogeneous traveling wave equation to calculate the tangential electric fields at the interface. The region of subgrid must...