The Incentive Effects Of Phase Jitter Frequency Source Signal

Crystal Oscillators are widely used in different kinds of electronic devices in communication and radar systems. With the development of various technologies, quality of frequency source has been a key factor which affects the performance of diversified electronic systems. It admits of no delay to develop high stability Crystal Oscillator and enhance its phase noise index to reduce the effect of jitter to the performance of the whole system. At the same time, the technology of frequency synthesis is developing rapidly and it requires much better performance on its reference source-Crystal Oscillator. So, it is significant for practical applications and development of theory to make researches on Crystal Oscillator's phase noise and phase jitter, and improve its performance fundamentally.Firstly, this paper describes the development and status of crystal resonators. Its advantages as a frequency control component are presented. The basic principle of feedback Crystal Oscillator is analyzed. The basic concept of frequency stability is also introduced, following by the usual expression of phase noise in frequency domain and phase jitter in time domain. Further, we describe the origin of Crystal Oscillator's phase noise and phase jitter, also list a variety of its contributors.Secondly, we make an in-depth study and analysis in allusion to the given oscillatory circuit-Butler common base harmonic circuit. The detailed analysis of the dynatron which is the main noise source in the oscillatory circuit is also made, including how excitation affects the dynatron and crystal. Based on the analysis of transistor amplifier noise model, we select devices with low noise in reason. And the method how to reduce phase noise and phase jitter is also discussed. According to Leeson Model, which had proposed the relationship of noise between output and input in the feed-back oscillator, an experimental Crystal Oscillator circuit with high stability and low phase noise is designed. How the key device in the circuit affects the whole performance is analyzed in experiment.During the design, high frequency simulation tools, such as Advanced Design System (ADS) 2004A of Agilent Corporation and Serenade v8.7 of Ansoft Corporation,...