Composite left-handed meta-atom for tri-band operation

This paper introduces a compact composite meta-atom for S-, C-, and Ku-band applications, which shows left-handed characteristics at 0 degrees, 90 degrees, 180 degrees and 270 degrees structural rotations. The proposed structure provides wide bandwidth when the operating frequency is between 2.0 and 14.0 GHz. Additionly, the proposed meta-atom is designed by creating splits in the outer and inner square shape ring resonators, and a metal arm is placed at the middle of the inner ring resonator. The arm is also connected with the upper and lower portion of the inner ring resonator, and later, the design appears as an I-shaped split ring resonator. FIT based computer simulation technology electromagnetic simulatortool is utilized for the design, simulation, and numerical analysis. The measured results comply well with the simulated results of the meta-atom for every rotation angle. Owing to the effective medium ratio of 8.50 at 0 degrees and 180 degrees rotational angles and the figure of merit grater than 1.0, the designed meta-atom is compact in size and practically implementable.