Low Numerical Dispersion LOD-FDTD Algorithm

This work addresses the significant dispersion error in the locally one-dimensional finite-difference time-domain (LOD-FDTD) method by proposing a novel approach featuring isotropic dispersion, known as ID-LOD-FDTD. This method linearly weights the traditional Yee scheme and the isotropic scheme by using a determined weighting factor. Additionally, a scaling factor is used to further correct the normalized phase velocity, making it approach the exact value. The paper provides the derivation process of the dispersion formula for the new method. During the simulation process, the novel method is benchmarked against the traditional LOD-FDTD method, demonstrating the ID-LOD-FDTD method’s superiority in attaining more isotropic dispersion.