Characteristics of a New Carbon Nanotube Antenna Structure With Enhanced Radiation in the Sub-Terahertz Range

In this paper, a new antenna configuration is proposed to operate efficiently in the sub-terahertz frequency range (10-1000 GHz). The proposed antenna is composed of a bundle of single-walled carbon nanotubes (SWCNTs) surrounded by two dielectric jackets; the inner of which is dielectric foam with relative permittivity close to unity. The outer one is a metamaterial layer with permittivity much smaller than the free-space permittivity. Rigorous analysis shows that the metamaterial layer helps to reduce the axial propagation constant of the surface wave mode traveling along the antenna. The radiation resistance and the radiation efficiency of a resonant dipole antenna are derived. Numerical results show that these parameters are considerably enhanced at the sub-terahertz frequencies relative to the SWCNT bundle antenna.