Dielectric-tube-supported metal rod transmission line and its application to transition for 1mm coaxial connector at 80 GHz band

The dielectric-tube-supported metal rod transmission line was proposed with the aim to realize a low-loss and flexible transmission line at millimeter-wave frequencies. To feed the transmission line to conventional measurement equipment, a transition between that and 1 mm coaxial line was fabricated, and the transmission characteristics were evaluated taking the transition performance into account at millimeter-wave frequencies. First, the basic consideration about the higher order modes and the transmission characteristics of the analytical models was investigated. Next, the transition was fabricated, and the transmission characteristics as well as the transmission line were measured at 80 GHz frequency bands.