High-frequency electromagnetic field coupling to a long finite line with vertical risers

In this paper, we consider high-frequency electromagnetic plane wave coupling to a long finite line with vertical risers above a perfectly conducting ground, when the classical Transmission Line (TL) approximation is not applicable. We derive analytical expression for the induced current in the central part of the line, using the so-called asymptotic approach. The application of the asymptotic approach requires the knowledge of reflection and scattering coefficients for current waves in semi-infinite lines. To obtain these coefficients, we have used perturbation theory for the solution of Mixed Potential Integral Equation (MPIE). The obtained results are in very good agreement with numerical simulations.