Electromagnetic Field Analysis of the Three-Dimensional Finite-Difference Time-Domain Method in Spherical Coordinates

Abstract

This paper presents analysis of electromagnetic fields by using the finite-difference time domain(FD-TD) method in three-dimensional spherical coordinates which is constructed from a set of Maxwell’s equations. The details of formulations are shown and three main singularities,which occur due to’ spherical geometry, are described including their treatments. Some alternative easy-implementing radiation boundary conditions (RBCS) are also introduced. Then, a stability criterion for three-dimensional spherical coordinates and time step determinations are considered.Finally, effects of simulating RBCs on calculating field unknowns and behaviors of this F’D-TD algorithm due to different types of applying sources such as pulse and continuous wave, will be illustrated.