A potable platform to analyze EEG signal for transimting to mobile device via Wi-Fi

In this paper, we develop a platform of medical instrumentation for real-time electroencephalogram(EEG) measurement and analysis system. This platform obtains EEG signal from electrode sensors, analyzes the signal and transmits the result to mobile device via Wi-Fi. Because the changes of EEG signal on the scalp received by electrode are in very small range, the signal is amplified by designed circuits. Low pass filter is applied in order to eliminate the component of breathing and high-pass filter is used to remove power supply noise. The digital logic in FPGA transforms time domain signal into frequency domain signal using 256 point radix-2 decimation-in-frequency as an FFT algorithm. The platform has developed on the FPGA development board.