Compact elliptical open resonators in microwave generators

The development of high-speed communication system is associated with the practical mastering of the extremely high frequency band. One of the methods of raising spectrum characteristics of semiconductor oscillators is frequency stabilization by external high-Q resonator. The experimental investigations of quasioptical 8 mm wave band Gunn-diode oscillator based on an open resonator of essentially nonspherical geometry, namely, elliptical-toroidal open resonator (ETOR). Millimeter wave Gunn-diode source is made as a quasi-axial unit, which is positioned in the center of waveguide section. The possibility to excite high-Q oscillations of the "whispering gallery" mode is one of the useful properties of this type of resonator. The small dimensions, hard construction and high-Q factor of ETOR recommend it as an oscillation system of millimeter wave solid-state sources with the enhanced spectral properties.