Millimeter wave Gunn oscillators for low noise receivers

Restricted Access.Presented in this paper in the design and development of Millimetre-wave Gunn Oscillators for the 33-50 GHg and 75-110 GHz waveguide bande. 50-100mW CW output power hae been obtained in the 33-50 GHz band with commercially available packaged Gunn diode8 operating in a fundamental mode in a post-coupled waveguide oscillator circuit. Here than lO mW output ha8 been obtained over the frequency range 75-85 GHz with the Gunn diode operating in a harmonic extraction mode in a resonant-cap waveguide oecillator circuit. These oscillators, developed in connection with radio astronomy receivers, could provide a solid-state reliable alternative to the relatively expensive and short-lived klyetrone for local oscillator application in low-noise receivers