An Enhanced Total-Field/Scattered-Field Scheme for the 3-D Nonstandard Finite-Difference Time-Domain Method

The nonstandard finite-difference time-domain (NS-FDTD) method exhibits high accuracy at fixed frequencies, and, thus, proves to be a powerful means of the radar cross section analysis of scattering objects with complex shapes and materials. To this aim, significant enhancement can be pursued in its combination with the FDTD total-field/scattered-field (TF/SF) concept. However, the principal implementation characteristics of the latter in the NS-FDTD technique have yet to be elaborately studied, especially for electrically large domains or structures. Hence, in this paper, a new advanced TF/SF scheme for the 3-D NS-FDTD algorithm is developed and fully validated. Numerical results reveal that the proposed method, considering the features of the NS-FDTD operators, is far more efficient and versatile than the original FDTD one.