Reconfigurable graphene-based V-shaped dipole antenna: From quasi-isotropic to directional radiation pattern

In this paper, a compact reconfigurable V-shaped dipole antenna in THz frequency with two parasitic elements on the substrate of SiO2 is presented. The antenna is designed in the center frequency of 0.95 THz. Designs have been improved based on two modes of antenna radiation pattern: quasi-isotropic and directional pattern. For providing a quasi-isotropic radiation pattern, by making V-form of the dipole, the radiation pattern nulls in the lateral of the antenna is reduced as much as possible although two antenna parasitic elements also affect the antenna radiation pattern. In another mode, only by changing of graphene chemical potential, designing of the directive antenna with the same structure is proposed. In the first mode, physical structure and the angle between dipole arms are more determinative, while in the second mode size and positions of parasitic elements, as well as other mentioned parameters, are effective. In the first mode, quasi-isotropic radiation pattern antenna with changing of antenna gain below than 8 dB, and in the second mode a directional antenna with 5.3 dB maximum gain, and 6 dB F/B ratio is proposed.