中文摘要：

在传统的脑电系统中,脑电信号采集使用的是湿电极,需要配合导电膏使用,糊状的导电膏无论是使用前的逐个注入和使用后的清洗,都使得湿电极的使用不便。文中设计并实现了一种不需要涂覆导电膏、可直接佩戴的带有前置放大电路的爪式干电极传感器,可用于穿戴式脑电辅助康复系统。和湿电极相比,这种电极安放简便快捷,尽管其接触阻抗稍高,但通过主动前置放大器的引入,有效地降低了等效接触阻抗,改善了电极的信噪比,提高了电极抵抗运动及工频干扰的能力。经过实际的脑电信号采集实验比对,主动干电极表现出良好的记录特性,与商用标准头皮湿电极采集的脑电信号的相关系数是0.89;信噪比与商用湿电极接近（在3 d B附近）,比没有采用主动放大电路的干电极高10 d B以上。

英文摘要：

Neural electrophysiological signals acquisition is important information to assess mental health and reflect emotion and main source for brain-computer interface（BCI）.In traditional BCI system,wet electrodes were used in brain electrical signal acquisition and conductive gel was coordinated.Paste conductive paste from one by one before using injection and after use,cleaning,making the use of wet electrode was rather inconvenient.This paper reported a claw-like dry electrode sensor with a preamplifier,which can be used for wearable electrical auxiliary recovery system.It can be worn more easily and quickly than the wet electrode.In spite of its slightly higher contact impedance,by introducing a preamplifier circuit,the signal-to-noise ratio（SNR） of the active dry electrode was effectively increased and the ability of anti-interference is improved.The test results demonstrate the good performance of the proposed active dry electrode.Through actual EEG acquisition experiments,active dry electrode shows good record characteristics.The correlation coefficient between the EEG waveforms recorded by the commercial wet electrode and the proposed active dry electrode is 0.89.The SNR of the active dry electrode is close to commercial wet electrode（near the 3 d B）,substantially improved 10 d B compared with the same dry electrode without the preamplifier circuit.