Transmission line studies for ITER compatible reflectometers

Corrugated circular transmission lines are considered as high performance, low loss, broadband lines for reflectometry on ITER. These lines are proposed as a possible solution for the equatorial low-field-side system and as a part (receiver-vacuum vessel) of the transmission lines for the high-field side and the out-of-midplane reflectometer system, because of their restricted access. Theoretical and experimental studies show the good properties of these lines: low losses, a smooth characteristic transmission, and a Very low level of parasitic reflections. Quasioptical systems are also proposed as a solution for the coupling of several microwave emitter receivers, working in a fundamental waveguide, into a single broadband corrugated line. (C) 1997 American Institute of Physics.