The Design Of 16-channel EEG Acquisition And Wireless Transmission System Based On STM32

The 21st century is an era of burgeoning brain science research.As a window for human beings to explore brain science,EEG signal acquisition equipment has important research value in clinical medicine,brain computer interface and other fields.With the concept of "wearable medical device" proposed,users' requirements for the performance and portability of EEG signal acquisition equipment are gradually improved.In order to improve the accuracy,portability and endurance of EEG acquisition system,a 16 channel EEG signal acquisition and wireless transmission system based on STM32 was designed and developed.The system has the functions of EEG signal acquisition and filtering,and can send the EEG signal to the host computer through wireless local area networks(WLAN)for real-time waveform display.The hardware design of the system was based on the right-leg drive circuit and highprecision analog-to-digital conversion principle,and used ADS1299,STM32F207 and Wi-Fi module as the core to complete the hardware circuit design of EEG signal acquisition and wireless transmission system.Based on the hardware,a set of C language driver code based on the STM32F207 microcontroller was designed using the MDK-ARM integrated development environment to realize the control,monitoring and management of other peripheral devices on the EEG acquisition board;The graphical user interface(GUI)design of the system was conducted based on Lab VIEW on the upper computer side,which realized functions such as data reception,data processing,digital filtering and waveform display,and provided the human-computer interaction interface.After completing the overall design,the system noise,power consumption,transmission distance and other parameters were measured,and a set of EEG signal test scheme was designed to fit the practical application scenario.The reliability of EEG collection by the designed system was verified through the verification experiments of human spontaneous EEG and steady-state visual evoked EEG.The final experimental results showed that when the sampling rate of the system was 1000 SPS,the transmission distance can reach 60 m,and the noise of each channel was less than 1?V,which met the standard of EEG acquisition equipment;at the same time,the measurement of human EEG proved that the system can effectively and accurately detect human EEG information.