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.