在目前的醫療儀器上來看，生理監測系統著重於診所或醫學中心內的病患生理監測，監測生理資訊需於特定的地點進行，生理監測儀器也有昂貴且不易攜帶的缺點。由於現代人生活發展快速且忙碌，居家穿戴且可攜式的病患監測系統也受到重視。穿戴式病患監測系統可應用於居家健康照顧，移動照護，身心障礙照護及個人生理數據監測等，主要應用於非急性病患的健康狀況追蹤及預防，以減少不必要的後續治療成本浪費，是預防勝於治療的觀念。
血氧飽和濃度計是使用光學元件來達到非侵入式的血氧飽和濃度監測儀器。依據微型化及無線傳輸的目的，需發展小型且可攜式的健康照護系統，因此需研究出連續性的健康照護監測及病人緊急預防裝置。由於發展此監測系統的需求，感測介面電路需減小面積及易於攜帶，且須減小光體積變化波形的干擾。最大的干擾來源來自於身體的動作干擾，因此減小動作干擾是非常重要的發展技術。
在本篇論文中，介紹了可攜式的感測介面電路及減小動作干擾之計算方法，感測器的部分使用綁帶式的方式來量測光體積變化波形。為了達到可攜式的目的，轉阻放大器、發光二極體驅動電路、類比開關、濾波電路這些量測元件被整合在一張印刷電路板。此外並把低通濾波器、帶通濾波器及帶拒濾波器以轉導電容濾波器的方式，使用TSMC 0.18μm的製程進行微型化。最後，本研究有別於傳統的660nm與870nm兩種波長外，另增加800nm的波長並產生參考訊號以修正人為動作干擾的問題；並且針對目前傳統兩波長脈動式血氧量測方法做改進；在減低人為動作干擾雜訊的部分，則使用正規化最小均方法來做適應性濾波器的演算法，並使用主動式雜訊消除的概念來做減低動作干擾的實作。

A pulse oximeter is a noninvasive oxyhemoglobin saturation monitoring instrument with optical components. When developing miniaturization and wireless communication technologies, small sized portable health care system are demanded. Therefore, continuous health care monitoring and precaution device for emergency are required for the patient. To develop the device on these demands, the sensing interface circuit is requested to minimize for protable reason and the photoplethysmographic to be reduce noise. The major source of noise is body motion, for this reason, motion artifact reduction is the key technique to develop.
In this paper, a portable sensing interface circuit and a motion artifact reduction method was proposed. The device had a shape of the finger band, which measured the photoplethysmographic on the finger. For the purpose of a portable device, components of the transimpedance ampligier, LED driver, analog multiplexer, and filters, were integrated into a printed circuit board. Moreover, the transconductance-C filter of low-pass filter, band-pass filter, and notch filter, were integrated into a chip using TSMC 0.18μm technology. Finally, this research presents a motion artifact reduction method with correction of optical calculation and active noise cancellation method with a reference signal to reduce signal distortion by body motion.

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