A fractional-N phase-locked loop synthesizer optimized for microwave Q-Meter application

This paper presents a design process of a fractional-N phase-locked loop frequency synthesizer dedicated to use in a microwave Q-Meter device. The requirements for this application and components selection criteria have been stated. The optimization was mainly focused on minimization of the phase noise and the overall time necessary to change the output frequency. Its value of 71 μs has been measured using a sensitive method based on high-Q microwave resonator and RF power detector.