Spectral analysis of negative refractive index metamaterials utilizing signal processing techniques and time-domain simulations

In this paper, signal processing techniques, mostly used for the Direction of Arrival (DoA) estimation in smart antenna systems, are combined with time-domain simulations in order to perform dispersion analysis of Negative Refractive Index (NRI) metamaterials. The time-domain response of infinite arrays of unit cells giving rise to NRI metamaterials is calculated using the Finite Difference Time Domain (FDTD) method together with Periodic Boundary Conditions (PBC). Subsequently, the correlation method, the MUSIC algorithm and the Matrix Pencil method are applied to the FDTD results and the resonances of those structures are estimated. A comparative study of the aforementioned algorithms is performed and the advantages of the Matrix Pencil algorithm are pointed out.