针对岩石电磁实验研究需要，构建专用岩石电磁辐射信号观测系统。铜板电容传感器的采用，将观测的频率带宽由固定点频拓宽至2.5 kHz-800 kHz的宽频带范围；PXIe-6368数据采集卡的应用，消除了PAC声发射仪的带通滤波和波形前端滤波功能对信号的影响，使观测系统可以记录到原始的EME信号。通过人工信号和岩石加载实验，对观测系统进行检验，发现：该观测系统可以采集2.5 kHz-800 kHz频带范围内0.1 mV以上EME信号，具有每通道最大2 M采样率、最多16通道同步采集功能。本套电磁辐射信号观测系统可以用来检测岩石加载过程中产生的EME信号，也可用于多种岩石物性参数的多通道同步采集。
An improved observation system is proposed to detect electromagnetic emissions produced by rocks during load compression experiments. It is found that the use of capacitive sensors widens the frequency bandwidth from 2.50 kHz to 800 kHz and the PXIe-6368 data acquisition card eliminates the effects of band-passing and waveform fltering, allowing the system to record the complete electromagnetic emission. The system is capable to detect signals above 0.1 mV amplitude with a maximum of 2 M sampling rate per channel. Because of the multi-channel input, up to 16, emissions can be detected simultaneously with various petrophysical parameters.
2017,38(3): 88-92 收稿日期：2016-02-26
DOI：10.3969/j.issn.1003-3246.2017.03.015
基金项目：国家自然科学基金项目《岩石破裂过程中电磁辐射的实验研究》（项目编号：41004029）
作者简介：何明文(1986-),男,硕士研究生,内蒙古锡林郭勒盟人,主要从事岩石加载实验电磁辐射研究工作。E-mail:hemw989@163.com.
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