Mechanical Tuning Properties of Waveguide-mounted Resonant-cap IMPATT Oscillator at Ka-band

Abstract

The paper describes the studies of the tuning properties of an indigenously developed resonant-cap continuous wave IMPATT oscillator at Ka-band by changing circuit susceptance through mechanical tuning. It was observed that output power of a resonant-cap IMPATT oscillator passes through a maximum at a particular frequency for a given diode with an optimum combination of cap diameter and cap height. An empirical relation has been found between cap diameter and wavelength of the optimised oscillator, which agrees with the theoretical relation. The effect of sliding short tuner position on the oscillator at optimised condition and the phenomenon of frequency jump in certain positions of sliding short have been studied.