A novel 3-D CPFDTD scheme for modeling grid nonconformally aligned transmitter structures

In this paper, a novel three-dimensional (3-D) subcell algorithm for modeling metallic objects which are nonconformally oriented within the finite-difference time-domain (FDTD) grid is proposed. The generally applicable algorithm is based on the contour-path (CP) technique and enables, in combination with an enhanced nonconformally aligned source model, a more accurate spatial representation of antenna structures than the common staircase approach. To evaluate the performance of the new algorithm, the simulation results are compared with the classical staircase approach for dipole antennas as well as for a generic phone. Significant improvements were achieved for all antenna parameters from the near and far field, i.e., feedpoint impedance, radiation pattern, and field distributions.