FDTD and MoM modeling of power from perpendicularly oriented, electrically small TM dipoles

Abstract

In earlier work we compared and contrasted analytic power calculations obtained using the time dependent Poynting theorem (TDPF) and the frequency domain complex Poynting theorem (CPT). We concluded that the complex Poynting theorem is an inadequate basis for a full description of power in a radiation field. In this work we use widely accepted frequency and time domain numerical techniques, the MoM and FDTD respectively, with the corresponding frequency or time domain versions of the Poynting theorem to illustrate the differences in calculated powers. The 'correctness' of the time domain results are checked in the following manner. We take the discrete Fourier transform of the time domain fields obtained via FDTD (the same time domain fields used with the TDPT to determine the time domain power), and combine the complex phasor values of the fields with the CPT to determine the frequency domain power: the frequency domain results determined in this fashion are in complete agreement with those obtained via MoM and CPT.