控制海底电磁激发脉冲发射的时间同步技术

The technique of time synchronization operation to control marine electromagnetic emission

为达到海洋可控源电磁探测和远参考测量的目的,研究控制海底电磁激发脉冲发射的时间同步技术,包括发射前与GPS的对钟技术和发射中的同步技术,保证仪器工作的时间和公共的时间基准GPS信号保持精确一致,为后期的数据处理解释提供统一的时间坐标.对钟技术是指,在海洋调查船上完成仪器内部RTC芯片分频所得的秒脉冲信号RTC_PPS与GPS秒脉冲信号PPS时钟沿的同步;同步技术是指,海底工作过程中,仪器在预定的时钟沿将可控源信号精确发射出去.本论文采用CPLD芯片、RTC芯片、GPS模块和AVR单片机来完成对钟和同步模块的设计.

In order to measure the marine controlled source electromagnetism and realize the remote reference detection, the technique of time synchronization operation to control marine electromagnetic emission is needed, insuring that the internal clock in the instrument is according to the GPS clock and providing the same time reference for the data processing. The lock GPS is that, the synchronization operation between the RTC_PPS which is from RTC and PPS that is from GPS on the investigative ship. The synchronization operation is the exact emitting operation at the right time in the working process. These modules are designed by CPLD chip, RTC chip, GPS module and AVR microcontroller.