Experimental verification of metamaterial loaded small patch antennas

Abstract

Purpose\ud – Metamaterial unit cells composed of deep subwavelength resonators brought up new aspects to the antenna miniaturization problem. The paper experimentally demonstrates a metamaterial-inspired miniaturization method for circular patch antennas. In the proposed layouts, the space between the patch and the ground plane is filled with a proper metamaterial composed of either multiple split-ring or spiral resonators (SRs). The authors have manufactured two different patch antennas, achieving an electrical size of λ/3.69 and λ/8.26, respectively. The paper aims to discuss these issues.\ud \ud Design/methodology/approach\ud – The operation of such a radiative component has been predicted by using a simple theoretical formulation based on the cavity model. The experimental characterization of the antenna has been performed by using a HP8510C vector network analyzer, standard horn antennas, automated rotary stages, coaxial cables with 50 Ω characteristic impedance and absorbers. Before the characterization measurements we performed a full two-port calibration.\ud \ud Findings\ud – Electrically small circular patch antennas loaded with single layer metamaterials experimentally demonstrated to acceptable figures of merit for applications. The proposed miniaturization technique is potentially promising for antenna applications and the results presented in the paper constitute a relevant proof for the usefulness of the metamaterial concepts in antenna miniaturization problems.\ud \ud Originality/value\ud – Rigorous experimental characterization of several meta material loaded antennas and proof of principle results were provided

Quadrupolarisability extraction for planar metamaterial scatterers via far-field response

“…Overall, the extraction of quadrupolarisability a xzx E and the addition of the respective quadrupole in the scattering model, pushes the multipole representation up to the level of l =2-2l =3, which is a promising improvement to the conventional l =4 dipole approximation limit (Karamanos and Kantartzis, 2018). Therefore, nanoparticles that possess quadrupole resonances and only the q xz moment can, now, be very accurately and consistently represented through polarisabilities for a large assortment of metamaterial or metasurface applications (Boratay Alici et al, 2013;Castaldi et al, 2013;Liu and Kivshar, 2018).…”