射电天文研究组知识库

介绍了VHF天线阵的时间频率系统构架,包括标准10 MHz信号和采样器所需时钟驱动的产生,以及基于GPS网络授时两个不同采样控制计算机中的时间比较方案,以确保接收采样数据的两台计算机的系统时间相同,从而保证存储数据的时标准确。授时策略研究基于Lab VIEW图形化编程平台,编写时间对比软件,该软件获取需要校时两台计算机的系统时间,经过分析对比确定两台计算机出现时间偏差的时长。最终实验结果表明该方法能自动校准局域网内计算机的系统时间,精度能达到0.1 s以下。

A time⁃frequency system architecture of the VHF⁃band antenna array，is introduced. The generation of standard 10 MHz signal and clock driving signal needed by the sampler，and a scheme of time comparison between two sampling and control computers based on different GPS network time services，which can ensure that the two computers receiving the sampling data have the same time and guarantee that the time scale of the storage data is accurate，are presented also in this paper. The study on the time service strategy is based on the LabVIEW graphical programming platform. The time comparison software was compiled to obtain system time of the two computers needing timing. The time length of the time deviation existing in the two computers is determined with the analysis and contract. The experimental results show that the scheme can automatically calibrate the system time of the computers in the LAN，and its deviation is less than 0.1 s.