A 93 GHz-Dielectric Resonator Oscillator

The set-up and performance of a 93 GHz dielectric resonator stabilized GaAs Gunn oscillator is described. The oscillator performs in the 2nd harmonic mode: Its fundamental frequency is stabilized by the dielectric resonator while only the harmonic frequency is coupled to the output. Besides of the very compact and low cost arrangement, this novel design offers the possibility to compensate the thermal frequency drift by properly choosing the temperature coefficient of the resonator material. The unloaded Q factor of the commercially available TE011+8 cavity was measured as ¿ 2700. The improvement of the phase noise amounts to ¿ 27 dBc compared to the unstabilized oscillator. An output power of 30 mW has been achieved using a Gunn diode capable to produce 50 mW at 94 GHz.