Intelligent PLL Using Digital Processing for Network Synchronization

By combining the advanced technologies of a crystal oscillator, LSI, and a computer, an intelligent phase-locked loop (PLL) which uses digital processing (DP) can be created. This kind of PLL, which is referred to here as DP-PLL, includes a microprocessor and a digitally controlled crystal oscillator. It features excellent performance and countermeasures for disturbances of the input signal by stored program control. In this paper, implementation and performance of the DP-PLL are presented with the aim of application in a master-slave network synchronization system.