Total-Field/Scattered-Field Separation Based on $H$ -field Correction for the Nonstandard Finite-Difference Time-Domain

The nonstandard finite-difference time-domain (NS-FDTD) methodology is a very competent numerical tool for the radar cross section (RCS) analysis of scattering objects with complicated geometries and electrically large sizes, due to its high accuracy at fixed frequencies. During the RCS calculation via the typical FDTD scheme, the total-field/scattered-field (TF/SF) approach is generally used to separate the SF from TF simulation region. However, existing TF/SF separation algorithms for the NS-FDTD method are rather laborious for practical arrangements. Therefore, we develop a new TF/SF separation technique, solely based on H-field correction, and apply it in both cubic- and rectangular-cell computational domains, which discretize demanding structures. In all scenarios, the proposed algorithm is found to be superior over previously derived procedures, while, concurrently, remaining much simpler in its overall NS-FDTD implementation.