Precision-and-flexibility optimized wearable dual-channel EEG acquisition system

Abstract Most wearable EEG acquisition devices rely on EEG caps and demand to carry a wired signal acquisition box. For many out-of-laboratory monitoring applications, it is necessary and significant to develop a novel flexible wearable EEG acquisition system with superior characteristics of small size, high precision and easy to wear. This technology combines a high-precision EEG signal acquisition chip with a high-input impedance preamplifier to enhance the quality of EEG signal acquisition. In addition, flexible printed circuit board and silicone encapsulation process are applied to ensure high flexibility with the best fit for the head. The classical experiments show that when the input voltage of the system is 10 μV–10 mV, the short-circuit noise is lower than 1.5 μV, the output error is smaller than 10%, the input impedance can reach 680 MΩ, and the dry electrode can obtain clear α waves in areas with hair. Additionally, to verify the accuracy of the system, synchronous EEG measurement experiments using the AD INSTRUMENT and the proposed device were conducted, and the correlation coefficient between these two acquired signals is 0.92. With optimized precision and flexibility, the wearable dual-channel EEG system can be conveniently applied in out-of-laboratory EEG monitoring.