Gaseous discharge plasma switching in oversized interference microwave switches

Abstract

The first results of the study of gaseous discharge plasma switching in oversized interference switches of X-band active resonant microwave compressors are presented. The switching occured in a mixture of argon and air at atmospheric pressure in the mode of spontaneous breakdown. The breakdown was initiated by a sizable conductive discontinuity represented by a section of thin copper conductor of different lengths not exceeding the working wave length. The section was introduced inside the gaseous discharge quartz tube into the switching arm of the switch through the below cut off circular waveguide. The tube formed the discharge gap in the arm and was located coaxially in the circular waveguide. The tube was located at the antinode area of the electric field standing wave parallel to lines of electric force. The threshold nature of effective switching was proved. The switching efficiency as a function of the conductor length is obtained. The model of the switch was proposed and analyzed by the scattering matrix method within single-wave approximation. The calculation results were in substantial agreement with the experimental data. The operation of two oversized switches in a cascade circuit was studied. It is shown, that in switching circuits of these type formed by one or several oversized H-tees, the switching identical to processes in a conventional switch based on a single-wave H-tee is possible.