An Optimized 3-D HIE-FDTD Method With Reduced Numerical Dispersion

Fast and accurate modeling of scatters with fine structural feature in one or two directions has significant practical and scientific importance. To fill such research gaps, a 3-D artificial anisotropy hybrid implicit-explicit finite-difference time-domain (AA-HIE-FDTD) method is proposed. The new algorithm is based on the introduction of AA parameters to the traditional HIE-FDTD method. The iterative formulations and theoretical stability condition are given in detail. The proposed method is an easy-to-use extension to HIE-FDTD with the nearly unchanged Courant-Friedrich-Levy condition. Numerical results indicate that the proposed method has higher accuracy under the same cost of time and memory, when compared with the conventional HIE-FDTD method. In addition, the proposed method allows for larger time-step size than the conventional FDTD method, which implies reduced time cost.