A parameter optimized 3-step LOD-FDTD method based on the (2, 4) stencil

A parameter optimized 3-step locally one-dimensional finite difference time domain (LOD3-FDTD) method based on the (2, 4) stencil is presented here. Stability analysis shows that the proposed method is unconditionally stable for all the real values of the parameters. To reduce the numerical dispersion error of the LOD3-FDTD method, two optimization schemes are proposed in this paper. Minimization of dispersion error along the axial directions and minimization of overall numerical dispersion error using global phase velocity error (GPVE) are done in the first and second optimization schemes, respectively. Both the optimization schemes significantly reduce the numerical dispersion error of the LOD3-FDTD method.