Analysis of a Dielectric-Covered Waveguide Slot Antenna Using the Spectrum of Two-Dimensional Solutions

This communication presents an effective and accurate method of computing admittance and resonant characteristics of a single longitudinal waveguide slot, radiating into a dielectric layer. The external magnetic field is computed using the spectrum of two dimensional solutions (S2DS) which reduces a three-dimensional (3D) problem to a 2D problem. S2DS method avoids involving double singular integrals while it only deals with single integral with simple point singularity which needs much less computational effort. The spectrum of the 2D solution is then inverse Fourier transformed to the spatial 3D one. The slot field is determined by Galerkin's method of moments (MoM), then the scattering coefficients and thus the resonant length and conductance are extracted. Computed results are in good agreement with other methods' and measurement data.