A tunable terahertz (THz) dual-band circularly polarized (CP) dielectric resonator (DR) antenna (DRA) is numerically analysed and implemented. Initially, an aperture coupled dual-band rectangular DRA is designed. This operates with the fundamental mode in the lower band and third order mode in the upper band and provides the linearly polarized response. The diagonal corners of the rectangular DR are truncated for obtaining the orthogonal degenerate components of the operating modes and thus the CP response is achieved. The tunability is achieved in the frequency response by applying a monolayer graphene material coating at the radiating surface of the chamfered DR. The antenna offers 10 dB impedance bandwidth of 18.41% (3.21 -3.86 THz) and 4.7% (4.77 -5.0 THz) along with 3 dB axial ratio bandwidth of 3.48% (3.38 -3.5 THz) and 1.39% (4.98 -5.05 THz). Furthermore, the proposed tunable dual-band THz CPDRA provides the gain of more than 6 dBic along with the radiation efficiency of more than 95% in each operating band.
NSTL
Elsevier
