FreeBCI: Android application for portable EEG signal acquisition system

EEG signals, as an neurophysiological indicator of brain activity, are crucial in clinical diagnosis. Most EEG machines on the market today are characterized by high costs, complex equipment, and limitations in usage scenarios. Therefore, finding a more convenient and cost-effective way to capture, process, and display EEG signals has become an important challenge worth addressing. In this work, we designed a portable EEG monitoring system and conducted multiple experiments to assess its feasibility and reliability. The system consists of data acquisition hardware and signal processing and analysis software. The hardware integrates multiple components with a streamlined design, while the software is developed for the Android platform, supporting data interaction via Bluetooth or Wi-Fi. Overall, the system enables real-time acquisition and display of EEG signal features, including time domain, frequency domain, and specific frequency bands, on smart mobile devices. We conducted a simulated EEG signal acquisition experiment by inputting signals with specified amplitude and frequency into the acquisition electrodes, and carried out a real EEG signal collection experiment for eye movement artifact detection with the assistance of volunteers. Performance metrics such as frame loss rate and single-frame processing time were measured and calculated. These experiments comprehensively demonstrated that the system can effectively and conveniently observe and analyze EEG signal characteristics.