Calculating Current Distribution on Full-Wave Dipoles Using the Method of Moments

The Method of Moments (MoM) is a numerical technique widely employed in electromagnetic field computations, particularly effective for determining current distribution on full-wave dipole antennas. This method transforms integral equations into matrix equations through discretization of continuous problems.

In full-wave dipole current distribution analysis, the MoM implementation follows three key computational steps. First, the dipole conductor surface or wire structure is discretized into multiple segments using basis functions. Then, an electric field integral equation (EFIE) is established and converted into a matrix equation using boundary conditions. Finally, the linear system is solved to obtain current coefficients for each discrete segment.

The primary advantage of this approach lies in its precise handling of conductor geometries and radiation boundary conditions, yielding results with high physical reliability. For full-wave dipoles as typical antenna structures, MoM accurately captures standing wave characteristics of current distribution, including the positions and amplitudes of current maxima (antinodes) and minima (nodes).

Practical implementation requires careful selection of basis functions and discretization density control. Piecewise sinusoidal basis functions are commonly adopted due to their clear physical interpretation and computational efficiency. Discretization density typically requires 10-20 segments per wavelength to ensure numerical accuracy, which can be implemented in code through adaptive meshing algorithms.

MoM results provide critical references for antenna design, including input impedance and radiation pattern parameters. While computationally intensive, this method offers indispensable value for understanding full-wave dipole operation principles and design optimization, with potential code acceleration through matrix compression techniques like the Adaptive Integral Method (AIM).