Optimized Analytic Field Propagator (O-AFP) for Plane Wave Injection in FDTD Simulations

Optimizations are proposed for the original frequency domain analytic field propagator (AFP) to source plane waves in a 1D/2D/3D total-field scattered-field (TF/SF) FDTD formulation. The proposed technique essentially produces no field leakage error (limited by-300 dB machine precision error) with finite sampling points dictated by temporal aliasing constraints. By taking advantage of the inherent 1D nature of a plane wave, the memory requirements for the original AFP are reduced significantly. The proposed optimized solution (O-AFP) greatly reduces the computational complexity by calculating a number of spatial fields of
O
(
N
) rather than
O
(
N

²
), which then makes the technique practical enough to include fully 3D simulations.