Switchable circular polarization in flower-shaped reconfigurable graphene-based THz microstrip patch antenna

Abstract

In the proposed article, the design of a flower-shaped reconfigurable graphene-based THz microstrip patch antenna is presented. The cross-shaped slot in the center of the antenna promises the realization of circular polarization. The configuration of the structure is considered in such a way that each component of the body has the ability to realize a different behavior for the far-field due to the changes in the chemical potential values and in fact the Fermi energy. In fact, an antenna with the ability to switch between right-handed circular polarization and left-handed circular polarization has been proposed in the THz frequency band. According to the design, the resonance frequency is located at 0.77 THz. The main purpose is polarization adjusting through chemical potential changes. At the same time, the physical structure of the antenna remains fixed and intact. Next, an antenna with a suitable matching range of 0.6 THz through 0.95 THz has been achieved. It is possible to control its polarization in two circular polarization modes, right-handed and left-handed. Suitable axial ratio is about 3 dB, which is obtained in the range of 0.62 THz through 0.64 THz. The addition of layered patches has enabled polarization switching. The output of S₁₁ is less than − 10 dB in the range of 0.6 THz through 0.95 THz. which represents the optimal matching. And, the outputs of radiation efficiency, far-field directivity radiation pattern, 2D and 3D radiation patterns, E-field distribution, surface current distribution H-field distribution, and current density distribution have been reflected.