Analysis and Design of Metamaterial Antenna using the Theory of Characteristic Modes

In this paper, a Metamaterial unit cell is proposed for microwave applications. The structure is made up of an outer ring with four capacitive loads and two inside parts perpendicularly connected with a square in the center. A set of unit cells are associated with the bowtie antenna to improve their performances using the Theroy of Characteristic Modes. By adding the Metamaterial, the antenna performances are improved, such as the gain which increased by 3 dB, and the bandwidth that can reach 49 %.