Ultra Low Noise Dielectric Resonators Oscillators with Tuning at Ku Band

This paper describes the design of very low noise, tunable, Ku band Dielectric Resonator Oscillators (DROs) presenting phase noise performance of -100 dBc/Hz at 1 kHz offset and -130 dBc/Hz at 10 kHz offset. SiGe based transistors are used for the oscillator sustaining amplifiers which offer circulating power 10 dBm and gain of 4 dB per stage as well as low flicker noise corner between 10 kHz and 40 kHz. The resonator has unloaded Q around 15,000 at operating frequency and is then optimized and coupled to the amplifiers for minimum phase noise where Q_L/Q₀=1/2 hence S₂₁=-6 dB. In order to incorporate tuning, phase shifter is also investigated. The phase noise measurement system is presented using two DROs beating at the same frequency.