臺灣博碩士論文加值系統

氧氣是人們生活中不可或缺的一部分，若是缺乏足夠的氧氣會影響細胞的新陳代謝甚至死亡，因此脈博血氧飽和度(oxyhemoglobin saturation by pulse oximetry, SpO2)為人體健康的一個重要指標，市面上的穿戴式裝置絕大多數擁有量測血氧功能。反射式血氧量測的需求逐漸增加，開發者研發穿戴式裝置的血氧濃度需透過血氧模擬器進行驗證。現今大多數是穿透式血氧模擬器，並且價格非常昂貴，因此本論文設計出低成本反射式模擬器來提供開發者使用。
本研究中，使用嵌入式Linux系統進行開發，使用音效卡DAC16 bit 192KHz 取樣率來控制一組 LED 紅光和紅外光進行光體積變化描記圖法(Photoplethysmography, PPG)訊號模擬，透過 Fluke Prosim8 穿透式血氧模擬器將量測的數據來對本系統所產生的光體積變化描記圖法模擬訊號進行校正，並能模擬血氧濃度： 70%~99%、訊號強度： 4%~10%。
本論文完成反射式血氧模擬器，透過Fluke Prosim8來驗證血氧濃度差異，在SpO2在70%~99% PI大於7以上有小於1.5%的血氧濃度誤差，在Apple Watch與Garmin Watch 上量測無效，可能是因血氧量測需要多組光源進行量測，無法得知穿戴式裝置相對應收光的時間所造成無法量測之情況。

Oxygen is an indispensable part of people's life. If our body’s oxygen is insufficient, it will affect the cell metabolism and even die. Therefore, oxyhemoglobin saturation by pulse oximetry (SpO2) is an important indicator of human health, and most of the wearable devices on the market have the function of measuring blood oxygen.
The demand for reflective blood oxygen measurement is gradually increasing. The blood oxygen concentration of the wearable device developed by the developer needs to be verified by the blood oxygen simulator. Today, most transmissive blood oxygen simulators are very expensive, so this paper designs a low-cost reflective simulator offer developers using.
In this study, The embedded Linux system is used for development, and the audio DAC 16 bit 192KHz sampling rate is used to control a set of LED red light and infrared light for Photoplethysmography (PPG) signal simulation, through Fluke Prosim8 transmissive blood oxygen simulator uses the measured data to correct the photoplethysmographic analog signal generated by the system, and can simulate blood oxygen concentration: 70%~99%, signal strength: 4%~10% .
This paper completes a reflective blood oxygen simulator, and uses Fluke Prosim8 to verify the difference in SpO2. When SpO2 between 70% and 99%, and PI level greater than 7, there is a blood oxygen concentration error of less than 1.5%. The measurement on Apple Watch and Garmin Watch was invalid, probably because the blood oxygen measurement required multiple light sources for measurement, and the timing of the corresponding light received by the wearable device was not known.

摘要-i
ABSTRACT-ii
致謝-iv
目錄-v
表目錄-viii
圖目錄-x
第一章 緒論-1
1.1 前言-1
1.2 研究背景與動機-2
1.3 論文架構-2
第二章 背景知識與相關研究-4
2.1 光體積變化描記圖(Photoplethysmography, PPG)-4
2.2 血氧飽和度(Oxyhemoglobin Saturation)-5
2.2.1 血氧飽和度簡介-5
2.2.2 血氧飽和度計算方法-6
2.3 數位訊號處理-8
2.3.1 傅立葉轉換(Fourier Transform)-8
2.3.2 巴特沃斯濾波器(Butterworth Filter)-9
2.3.3 多級移動平均濾波器(Multiple Moving Average Filter)-10
2.4 Rock PI S(RK3308)平台介紹-11
2.5 PPG感測器(AFE4900) 介紹-14
2.6 Fluke Prosim8多功能生理訊號模擬器-17
2.7 相關研究回顧-18
2.7.1 文獻回顧介紹-18
2.7.2 文獻回顧總結-26
第三章 系統設計與實驗方法-27
3.1 系統架構-28
3.2 系統流程-30
3.3 硬體架構設計方法-32
3.3.1 無源一階低通濾波器電路設計-33
3.3.2 訊號放大電路-36
3.3.3 電壓電流轉換電路-37
3.3.4 解多工器電路-38
3.4 軟體設計方法-39
3.4.1 Rock PI S核心撰寫與編譯方法-39
3.4.2 時序校正方法-45
3.4.3 模擬血氧濃度變化方法-47
3.5 驗證本系統方法-49
3.5.1 驗證LED打光時序-49
3.5.2 驗證光體積變化描記圖訊號方法-51
第四章 結果與討論-52
4.1 光體積變化描記圖訊號結果與評估-52
4.1.1 本系統模擬光體積變化描記圖訊號分析之結果-52
4.1.2 本系統模擬光體積變化描記圖訊號分析之討論-59
4.2 血氧濃度分析結果與討論-60
4.2.1 穿戴式裝置與本系統血氧濃度分析之結果-61
4.2.2 穿戴式裝置與本系統血氧濃度分析之討論-63
第五章 結論與未來展望-64
5.1 結論-64
5.2 未來展望-65
參考文獻-66
附錄-71

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