History and perspectives of THz components and circuits using oversize dielectric-lined waveguides

A set of quasioptical (QO) components was developed for designing the THz radio measuring circuits for plasma diagnostics, radar engineering, spectroscopy, non-destructive testing, biomedicine, education, etc. Components and circuits were built on the basis of oversized dielectric-lined low-loss waveguides with hollow core and included attenuators, phase shifters, polarization-plane rotators etc. The working wave was characterized by the plane phase front, linear polarization, and axially symmetric amplitude distribution. The mode field maximum lies on the waveguide axis and field magnitude smoothly falls toward the waveguide walls. Comparatively to other similar components, the outer metal shell provides protection from environmental impact and increases rigidity. Each component can be joined one to another in one circuit using flanges, pins and clamps.