交互式卫星通信系统中时间同步技术研究

Research of Precise PCR Generation in DVB-RCS System

通过对DVB-RCS系统的介绍揭示了全网时间同步在整个系统中的重要性;通过对DVB-RCS标准规定的全网时间同步流程的分析,明确了主站提供的定时信号——节目时钟基准(PCR)的准确与否是时间同步性能好坏的重要前提;通过对定时信号产生、传输过程的分析,确定了影响定时信号准确度的因素,提出了产生精确定时信号的方法;通过对比分析得出了采用检测替换法消除抖动延迟较好的结论。

This paper reveals the importance of the time synchronization in DVB-RCS network by introducing how the DVB-RCS system works, analyses and identifies that the precision of the main station＇s time information- -programmed clock reference is the most important influence on time synchronization. The paper also investigates the process of PCR＇s generation and transmission, and then presents some algorithms to eliminate the dithering delay of the PCR. Compared to other methods tabled in the paper, the detect-and-replace method is a better way to eliminate the dither delay.