Transmission characteristics of NRD guide as a transmission medium in THz frequency band

The NRD guide is a promising candidate for a millimeter-wave transmission media. In this paper, the NRD guide was theoretically designed at THz frequencies and its performance was evaluated from the viewpoint of transmission characteristics. At first, polyethylene with a relative dielectric constant of 2.3 was selected as a material of the dielectric strip, and the transmission loss was calculated as functions of loss tangent of the dielectric strip and conductivity of the metal plate. It was found that the transmission loss of the NRD guide was lower than that of the coplanar waveguide, presented in several reports, because the transmission loss of the NRD guide was 1 dB/mm on average at a frequency of 1.5 THz.