Analysis of planar antennas using unconditionally stable three-dimensional ADI-FDTD method

A three-dimensional (3D) alternating direction implicit finite-difference time-domain (ADI-FDTD) algorithm is used to analyze a planar antenna. Two kinds of absorbing boundary conditions (ABCs) are first jointly employed for the ADI-FDTD algorithm and the way to apply the source excitation in ADI-FDTD is described. Numerical simulations show that the number of iterations with this ADI-FDTD can be at least four times fewer than with the conventional FDTD, without losing accuracy.