论文部分内容阅读
一引言近年来通讯技术的两项显赫成果——彩色电视播音遥控同步及时分制脉码调制系统的卫星同步——要求进一步发展压控振荡器的锁相环路理论。这两种系统的锁相环路中均有大的时延,特别是在播音遥控同步中此时延往往因传播距离及所用连接电缆的不同而异。时延对系统的动态特性影响很大,在上述两类应用中往往用一个相当慢的时间光栅及高精度振荡器来复盖信号时延的影响,以求出其数字或各别的解。尽管如此,一般对模拟时延锁相环最佳参数选择仍然极为关注,因为这样可以得出快速的解,并可在现有系统组件中扩大应用。
I. INTRODUCTION In recent years, two prominent achievements of communication technology - remote control of color television broadcasting and satellite synchronization of pulse code modulation system in time division - require further development of the phase locked loop theory of voltage-controlled oscillator. Both systems have large delays in the phase-locked loop, especially in broadcast remote synchronization, which often varies depending on the distance traveled and the connecting cable used. The delay has a great influence on the dynamic characteristics of the system. In these two types of applications, the effect of signal delay is often covered by a rather slow time grating and a high-precision oscillator to find the number or individual solutions. In spite of this, the best parameter choice for analogue-delay PLLs is still of great interest in general because of the quick solution that can be applied to existing system components.