Phase group characteristics and phase coincidence detection based phase noise measurement method

A novel phase noise measurement method is proposed based on phase group processing and phase coincidence detection. Using the regularity variation of the phase difference between frequency signals, phase group processing can be made without the normalization of the frequency signals. The phase group characteristics, such as phase group synchronization, and the regularity of phase coincidence detection between different frequency signals are revealed in this paper. Based on the phase group characteristics and phase coincidence detection, two adjacent phase coincidence points of the reference frequency signal and the measured frequency signal are used to generate the measurement gate. The fluctuation of the gate time between multiple consecutive measurement reflects the close-in phase noise. And the edge feature of phase coincidence detection fuzzy area can be used to obtain the far-out phase noise. Experiment results show that this method has the advantages in simpler structure, wider measurement band, smaller additional noise.