Computational aspects for the accurate and efficient analysis of periodic planar leaky-wave antennas

Design techniques for leaky-wave antennas usually require complex analysis methods for the rigorous characterization of the radiating structures as a function of the various geometrical and physical parameters involved. An increasing number of such antenna topologies are based on planar stratified configurations with suitable inclusions of periodic metallic or dielectric perturbations. The prediction of the leaky-wave parameters (i.e., phase and leakage constants, etc.) is a difficult task to achieve in an accurate and efficient fashion. In this connection, the present contribution is focused on the computational aspects related to an integral-equation approach to the problem based on a mixed-potential formulation. By means of specific asymptotic extractions, powerful acceleration techniques for the relevant scalar and dyadic Green´s functions are proposed and tested for different types and dimensions of periodicity. Numerical results are provided and discussed for various significant types of periodic structures.