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In this work, a characterization procedure of Artificial Magnetic Conductor (AMC) metasurfaces based on analytical expressions developed using the Generalized Boundary Conditions (GBCs) model is presented. The correlation between the surface susceptibilities of the PEC scatterers and the main frequency points used in the characterization of AMCs are established. Then the susceptibilities of square patch, square loop, Jerusalem cross and second iteration Minkowski fractal PEC scatterers are obtained by two sets of simulations and are used to calculate profiling frequencies and stability parameters. The detailed characterization procedure is presented and the flexibility and effectiveness of the proposed method are compared to full-wave numerical simulations. [ABSTRACT FROM AUTHOR]

This paper describes the integrated use of two design strategies for controlling the permittivity and permeability of a transformation electromagnetics two-dimensional cloak. This hybrid process permits more freedom in the choice of the constitutive properties, which could simplify the implementation with metamaterials. Because simplicity of materials and scattering performance are inherently conflicting characteristics, a multi-objective genetic algorithm is applied to optimize them. According to the presented results for a transverse-magnetic layered cloak, it is possible to have a good performance in terms of scattering even with an approximated reduced set of parameters with unitary axial permeability. [ABSTRACT FROM AUTHOR]

In this work, a design method for artificial magnetic conductor metasurfaces based on generalized boundary conditions is proposed as an alternative to analytic expressions and to conventional optimization approaches. First, the required surface susceptibility is analytically obtained by using generalized boundary conditions and the equivalent circuit model. Then, the geometry of the PEC scatterers is optimized to achieve the required transmission coefficient. The detailed design procedure is presented and its applicability is demonstrated through numerical examples. The proposed method is compared to analytical expressions and to standard optimization methods, showing better results in terms of flexibility and computational cost. Metasurfaces based on square patch, square loop and Jerusalem cross scatterers, mounted on different commercial dielectric substrates are studied for ISM band applications. The results have shown good agreement with the design requirements. [ABSTRACT FROM AUTHOR]

An out-of-plane coordinate transformation can avoid singular materials in a two-dimensional electromagnetic cloak. Based on numerical simulations of elliptical cylinders, in this paper we show that the use of two different constants to define the out-of-plane stretching can result in anisotropic materials with lower values and yet with a better scattering reduction for a given incident wave direction. [ABSTRACT FROM AUTHOR]

A frequency selective surface (FSS) composed of a periodic arrangement of meander line inclusions is numerically analysed. The study is presented with respect to the number of meanders and is a generalization of the U-shape (1-meander). A y-polarized incident wave is used to illuminate the structure. The results are obtained by the finite element method. By investigating the transmission coefficient, in this letter, it is seen that several stopbands may be exhibited within the operating frequency band and resonant frequency reduction can be associated with the number of meanders. For an incident wave with linear polarization, our findings suggest that the shift at the resonant frequency is also due to the increase in the effective length in the polarization direction of the incident wave. The validation of our model is performed by U-shape simulation already experimentally tested in other letters. A very good agreement has been achieved. [ABSTRACT FROM AUTHOR]