Novel Unconditionally Stable ADI-FDTD Method with Low Numerical Dispersion

A novel unconditional stable 2-D ADI-FDTD method with low numerical dispersion is introduced. The proposed method reformed the weighting factor and scaling factor of the isotropic-dispersion FDTD (ID-FDTD) for an optimized ADI-FDTD method, which can generate nearly the exact phase velocity for a single frequency. Compared with the optimized ADI-FDTD method, the numerical dispersion of the new method is significantly reduced.