A Fixed-Frequency, Tunable Dielectric Resonator Oscillator With Phase-Locked Loop Stabilization

Highly stable oscillators used for microwave measurement systems require both excellent long-term and short-term stability. The dielectric resonator oscillator (DRO) offers a unique combination of high performance and simple construction. Its drift and noise are already comparably low, but can be further reduced by phase-locked loop stabilization. In this work, the design and measurement of a low-cost DRO concept with a phase noise of −107.2 dBc/Hz at 10 kHz offset frequency and 12.8 GHz output frequency is presented. An electronic control loop reduces drift and phase noise of the oscillator resulting in a very low jitter of 29 fs.