Finite Phased Arrays of Dielectric-Loaded Parallel Plate-Fed Coplanar Slot Antennas: Singular Integral Equation Formulation With Highly Convergent Kernels and Nystrom Discretization

We study phased arrays of parallel-plate-fed slot antennas radiating through a common ground plane. The feeding parallel-plate waveguides are filled by stratified dielectrics, and the primary excitation may involve either TM or TE incident modes. The work is motivated by the need to obtain highly accurate and easily implemented algorithms, applicable even to large arrays, and by the need to shed further light on the resonance mechanism associated with the dielectric loadings. It is shown that an almost perfect matching efficiency is attainable even for electrically very narrow slot openings. For the analysis, integral equation formulations are used, which are discretized in the framework of rapidly converging Nyström methods taking full account both of the singularities of the kernels and the singularities of the fields at the edges. The efficiency of the algorithm can be enhanced by a sophisticated treatment of the kernel functions that helps to isolate their singular parts in closed form and to recast the remaining nonsingular parts into rapidly converging series.