本論文之研究目的為設計一個擷取生物微弱電壓變動信號的擷取系統，使用非侵入式方法量測，以腦電波Electroencephalogram, EEG）為信號源，經由貼於頭皮表面上的電極來量測腦電波信號，腦電波信號經過放大、濾波、和數位化等過程之後，這些腦電波信號量測點再透過串列通訊方式，將量測結果即時地以數位化格式傳給外界電腦處理。
在擷取系統所使用的信號量測硬體中，對於生物或人體微弱信號量測，如本文之腦電波擷取系統，雜訊的干擾易造成信號之無法量測或分析。若使用混合式系統單晶片，對每個量測點均使用一個獨立的可規劃類比與數位混合式系統單晶片(System On Chip，SOC) 設計成為獨立的嵌入式量測模組，同時此獨立模組化之設計亦可避免雜訊之入侵。
擷取系統整合了個人電腦與多個嵌入式量測模組，它們之間透過串列匯流排傳遞轉換資料，並且可以透過軟體來調整及控制擷取系統，使得量測時能得到高放大倍率以及最佳電壓準位的信號。擷取系統主要是量測腦電波對時間上的變化量。
本研究的擷取系統經由實際量測，當眼球擺動時，在頭部表面可以量測得細胞活動所呈現出變動的微弱電壓差信號，電壓準位變動量8.97µV。而系統雜訊的干擾控制於0.36µV以內。

In this thesis, a tentative Electroencephalogram(EEG) measurement instrument has been designed based on System-On-Chip(SOC).
The EEG signal is sensed by electrode plates and amplified by a pre-amplifier (INA321, product of TI) with 1063 voltage gain. The amplified signal is then sent to SOC(CY8C26233-24PVI) which contained programmable digital and analog circuits for other amplifying、filtering、and doing analog to digital conversion.
The programmable is accomplished via the uC of the SOC which accepted the commands from a PC controller. The PC controller is used to control the instrument and accepting the digital signals from the instrument and doing the post-processing, like display and storing the data. The designed instrument contains 16 channels and each channel is an embedded measure module. Each measure module contains electrodes, pre-amplifier one SOC and interface circuit.
The synchronization mechanism for multiple channel measurement is via interrupt technique. PSoC Designer Tool was used to design the system. The system’s noise is under 0.36uV.

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