Metamaterial lens design using characteristics modes

This paper uses a new methodology of analysis based on characteristic modes for the analysis of lenses formed by metamaterials. The individual cells are metallic cylinders aligned with the direction of propagation. The lens antenna consists of twelve capacitively-coupled unit cells distributed along a ring and illuminated by an open-ended waveguide with a metallic resonant ring. An efficient optimization process has been carried out in order to find out the optimum dimensions of the antenna. The designed lens has a high bandwidth and a maximum directivity of 14 dBi at 14 GHz.