【摘要】 电磁波阵列数据采集系统要配合井中大功率电磁脉冲源使用,为了能够严格同步发射地震波、采集反射波,需要精确的时间同步信号。主要论述在复杂可编程逻辑器(CPLD)的控制下,结合恒温晶振(OCXO),实现全球定位系统(GPS)失效情况时的精确时间同步。在设计中采用CPLD作为GPS和OCXO同步时钟的控制和数据处理CPU,加速数据处理进度,提高了同步精度,在GPS失效时实现秒脉冲的平滑切换。且用CPLD取代在同步时钟设计中应用较多的单片机结构,使系统更小功耗更低。更多还原

【Abstract】 Electromagnetic array data acquisition system should match the high-power electromagnetic pulse source in wells,in order to launch seismic waves and collect the reflected waves rigorously,simultaneously it required precise time synchronization signals.The conditions under the control of the CPLD were mainly discussed,in combination with Over Controlled Crystals Oscillator(OCXO),the precise time synchronization of global positioning system(GPS)was realized.In the design,CPLD is used as CPU and OCXO of clock synchronized control and CPU for data processing to accelerate the progress of data processing for improving the synchronization accuracy.The common MCU structure is replaced by CPLD for smaller and lower power consumption of the system.更多还原