Research On Multi-channel EEG Signal Acquisition And Processing System

In recent years, as a new way of human-computer interaction, the BCI(brain-computer interface) has drawn attention in area of control and entertainment. Many institutions and companies research on diversified operations based on EEG, such as wheelchair control by EEG for the disabled and EEG games design for healthy people. With the in-depth understanding of human brain, BCI will play an increasingly important role.EEG signal is a weak physical electrical signal and is difficult to acquire, so in BCI system, EEG acquisition system is very important to help acquire EEG from brain scalp and get the original EEG signals after processing.This design mainly describes the idea of EEG acquisition system, firstly introduces the development and current situation of EEG acquisition system, then introduces the basic knowledge of the EEG signals, such as the classification of the EEG signals. According to the characteristics of the EEG, we put forward the overall design requirements and implementation method in chapter 2. Then tells about the hardware design in detail in chapter 3, including how to design the preamplifier, right leg drive circuit and filter circuit, STM32 control circuit, AD collection, and USB transmission for communication between STM32 and PC. Chapter 4 is mainly about software design, tells about STM32 firmware program, USB driver and PC application. After completing the whole design, we use SSVEP to validate the performance of system in chapter 5. In chapter 6, we summarize the process and harvest in whole design and prospect for future improvement.