Hybrid-shaped single-loop resonator: a four-band metamaterial structure

The aim of this reported work is to demonstrate the feasibility of a miniaturised four-band metamaterial resonator which has potential use in the design of multiband microwave devices such as four-band mobile phone patch antennas. The suggested resonator topology is called the hybrid-shaped single-loop resonator (HSLR) as its unit cell is formed by the combination of square-shaped and triangular-shaped sections of a single piece metal loop printed on a planar low-loss dielectric substrate. The performance of this novel four-band HSLR structure is investigated in comparison to the circular, triangular and square-shaped structures, which are recently reported double or triple band single-loop resonators. Simulations are performed using two different full wave electromagnetic solvers, HFSS and CST Microwave Studio, with excellent numerical agreement.