Hasar, Ugur Cem; Buldu, Gul; Kaya, Yunus; Ozturk, Gokhan

A recursive algorithm is proposed to accurately extract the electromagnetic parameters of isotropic/bianisotropic metamaterial (MM) slabs of inhomogeneous structures. The algorithm is based on the recursive calculations of measured/ simulated forward and backward scattering (S-) parameters from previously extracted wave impedances and refractive indices of each homogeneous layer (except the analyzed intermediate layer) by a suitable retrieval method. There are two main advantages of our proposed method over existing extraction algorithms. First, it could retrieve the electromagnetic parameters of both isotropic and bianisotropic MM slabs. Second, it is applicable for electromagnetic parameter extraction of inhomogeneous structures. For validation of our method and assessing its accuracy over existing extraction methods, we used the simulation results of various inhomogeneous structures constructed by different isotropic/bianisotropic MM slabs (split-ring-resonator (SRR), SRR-wire, omega, and omega-wire). For completeness, the effects of noise present in S-parameters and iterative error (by increasing the value of iteration numbers) are examined to test the robustness of the proposed algorithm.

AtıfScopus43·WoS42·OpenAlex47

İncele

Hasar, Ugur Cem; Yildiz, Gul; Bute, Musa; Muratoglu, Abdurrahim

In this paper, we investigate a reference-plane invariant (RPI) method for electromagnetic property extraction of bi-axial bianisotropic metamaterial (MM) slabs. In order to obtain unique properties, we applied the frequency varying technique in order to determine the location of the slab within its cell. For validation of the proposed method, we first simulated and then measured scattering parameters of a MM slab constructed by split-ring-resonators, next extracted its electromagnetic properties, and finally compared extracted properties by those retrieved by another method which requires reference-plane information. From the comparison, we noted that whereas our proposed method correctly retrieved electromagnetic properties without knowing the value of reference plane transformation factors, the accuracy of the tested method was seriously influenced by any inaccurate reference plane information.

AtıfScopus7·WoS5·OpenAlex8

İncele

Hasar, Ugur Cem; Buldu, Gul; Barroso, Joaquim Jose

Metamaterials (MMs) are engineered material with electromagnetic properties not commonly seen by natural materials such as negative refraction and near-zero permittivity. These materials have interesting applications ranging from perfect lens and electromagnetic cloaks to leaky-wave antennas and shifters. For such applications, electromagnetic properties of MMs are needed to be known. In this study, we propose a waveguide method for accurate electromagnetic parameter retrieval of weakly-coupled MM slabs (the wavevector is normal to the plane of the metallic inclusions). To achieve our goal, new expressions for effective permittivity and permeability as well as the magnetoelectric coupling coefficient are derived. For validation of our waveguide method, we used the simulated scattering parameters of a MM slab composed of split-ring-resonator unit cells by using a commercial 3D electromagnetic simulation program.

AtıfScopus1·OpenAlex3

İncele