Trajectories of the singularities of a thin wire scatterer parallel to lossy ground

A Pocklington-type integro-differential equation is formulated for the current induced on a cylindrical scatterer near a finitely conducting ground. The Fresnel reflection coefficient for vertical polarization is employed to scale ground-reflected scattered radiation produced by the induced currents. This formulation is reduced to a system of algebraic matrix equations suitable for numerical evaluation through application of the method of moments. The singularity expansion method (SEM) is used to obtain the natural frequencies of the scatterer. Trajectories of these singularities (i.e., natural frequencies) are presented as a function of scatterer height-to-length ratio, ground conductivity, and relative permittivity.