Application of Low-Loss Transmission Lines with an EHF Radiometer in Gas-Dynamic Experiments

The possibility of using oversized rectangular metal waveguides as elements of the transmission line of an EHF radiometer, which is designed to study fast gas-dynamic processes, is analyzed. The results of a numerical simulation and experimental research of a flexible waveguide for coupling metal waveguides of standard and oversized cross sections, which is constructed on the basis of a dielectric waveguide, are presented. A quantitative estimation of the signal attenuation in the transmission line, which is a combination of a flexible waveguide and an oversized metal waveguide, is performed.