Filtering delay jitter in timestamp stream for clock’s drift compensation system

In time synchronization, poor stability of cheep crystal oscillator would wipe out all the efforts on reducing synchronization error while the cost of high stability crystal oscillator limits the using scope of measurement and control system. Therefore, the paper proposes a new analysis for time synchronization algorithms that compensating the drift of local clock by the use of timestamp stream, and the demonstrate process of it is also presented. By simulation, it shows that the delay in an industry Ethernet environment is jitter with a much higher frequency relative to that of a clock drift. And based on the simulation results, a conclusion issues that if the filter used in the digital PLL of the compensate system be carefully designed, all the jitter occur in the industry Ethernet will be filtered out to ensure the efficiency of the presented time synchronization algorithm. No assumption on constant timestamp period is necessary here while some other similar methods must keep to that assumption.