分布式多通道同步采集系统设计

为实现分布式微震采集系统中各个采集终端之间和同一采集终端多个通道之间的同步，设计了一种分布式多通道同步微震信号采集系统。利用了ADS1278解决了同一采集终端多通道之间的同步采集问题，同时使用GPS时钟同步的方法解决了不同采集终端间的同步问题，在GPS设计中提出了时钟分相算法测量1PPS信号和本地秒脉冲时间误差，通过PID算法计算得到恒温晶振的频率偏差控制量来调整恒温晶振，最终使1PPS信号和本地秒脉冲信号高精度同步，从而实现不同终端之间的采样时钟同步。实验结果表明，不同数据采集终端之间的同步精度优于500ns，实现了分布式多通道同步信号采集。

Distributed Multi-channel Synchronous Acquisition System Design

To achieve distributed microseismic acquisition systems among the various collection terminals and the same collection terminal synchronization between multiple channels, design of a distributed multi-channel synchronous microseismic signal acquisition system. Use a piece of ADS1278 to solve the same collection terminal between multi-channel synchronous acquisition problems. While using GPS synchronous clock solves the synchronization problem between different collection terminal. In GPS design, propose a phase algorithm measure the time errors between 1PPS clock signal and the local second pulse. Then calculate the OCXO frequency deviation amount of control by the PID algorithm to adjust the OCXO frequency. Eventually 1PPS signal and the local second pulse signal synchronize with high accuracy. Experimental results show that the accuracy of synchronization between the different data collection terminal is better than 500ns, distributed multi-channel synchronous signal acquisition.