Closed-Form Analysis of Artificial Dielectric Layers—Part II: Extension to Multiple Layers and Arbitrary Illumination

In this second part of a two-paper sequence, we present an analytical formulation to model artificial dielectric layers (ADLs) of finite height. We extend the method developed in Part I (IEEE Trans. Antennas Propag., vol. 62, no. 12, pp. 6256-6264, 2014) describing the single layer to the multilayer case, by including the higher-order interaction between parallel sheets in analytical form. From the equivalent impedance of the layers, we can construct a transmission line model that provides the spectral Green's function of ADLs in closed form. This allows to characterize the propagation through finite ADLs and to study the dispersion characteristics from the investigation of the Green's function singularities. Finally, by integrating the responses of a continuous set of plane waves, sources at finite distances from the ADL slab are treated. The method is validated by comparison with commercial electromagnetic solvers and experimental results obtained from a X-band prototype demonstrator.