Analytic fields of a focused beam with higher-order compensations for FDTD TF/SF formulation

This paper presents time-domain analytic fields of a focused beam with higher-order compensations for the finite-difference time-domain (FDTD) total-field/scattered-field (TF/SF) formulation. The higher-order compensations account for the FDTD numerical dispersion and the frequency-dependent field polarizations. With these compensations, the focused beam can be excited with minimal field leakage errors in the SF region. Numerical experiments are presented to validate the proposed fields and its compensations.