海底MT信号采集电路的设计

设计海底大地电磁信号采集电路，需考虑海底信号特征、海上作业以及海底环境等各种因素。分析表明，除遵循电路设计的一般原则外，海底大地电磁测量要重点解决微弱信号检测、智能化数据采集、海底环境监测和同步记录等4个方面的问题。在设计方案中，电路灵敏度达到微伏级；使用嵌入式计算机实现采集控制；对方位、倾斜、振动、温度等参数进行巡回记录；仪器的时钟精度精准到微秒。所研制的电路经过了室内模拟测试和海洋试验。首次采集到中国海域的大地电磁数据。

THE CIRCUIT DESIGN FOR THE ACQUISITION OF SEAFLOOR MT SIGNAL

During the circuit design for the acquisition of the seafloor MT signal, many factors should be considered, including the characteristics of the seafloor signal, the operation on the sea , the environment on the seafloor,and so on. Besides the normal principle of the circuit design, the instruments should be able to detect the feeble signal, acquire the data intellectualized, monitor the seafloor environment and record the data synchronistically. In the design scheme, the circuit sensitivity is set to the level in microvolt; the acquisition is controlled by the built|in computer; the parameters including direction, incline, vibration and temperature are recorded periodically; the time precision of the instrument is in the level of microsecond. The circuit had been tested by the experiments indoor and in the sea, and had recorded China's first sea|floor magnetotelluric data.