以多通道高取樣率無線傳輸架構測量脈波傳導速率

Measurement of Pulse Wave Velocity By Wireless Multi-Channel Body Sensor Networks With High Sampling

劉維昀(Wei-Yun Liou)

指導教授 ： 林康平

中原大學/電機資訊學院/電機工程研究所/碩士(2017年)

https://doi.org/10.6840/cycu201700788

摘要

脈波傳導時間(Pulse Transient Time, PTT)，對於生理訊號的分析是重要的參數，可用來估測心律變異(HRV)、血壓(BP)…等人體訊號，因此PTT時間的正確與否對於人體生理訊號的測量與估算有著重要的影響。論文中暫不討論交感神經或其他生理現象的影響，假設血液從心臟流經身體各部位的位置順序與距離長度皆不同且血流速於等速情形，測量人體四肢脈波傳導特徵的PTT，會因為測量位置的不同而具有時間上的差異，而PTT時間參數是對時間的觀察，因此更仰賴高速的取樣頻率作為基礎。
本研究論文目的是自製一套具有高速取樣頻率，最低可穩定在1KHz的無線人體感測系統，期望此無線傳輸系統能有效的應用在人體生理訊號測量。實驗完整測錄四位年輕健康受試者的四肢末梢脈波訊號(PPG)與心電圖訊號(ECG)，調整訊號取樣頻率，推算在不同取樣頻率之下的脈波傳導時間PTT，並分析討論人體四肢PTT之差異在不同取樣頻率之下的情形，是否可以辨識出脈波傳導上的時間差異。
實驗結果顯示，以心臟至左手末梢的PTT時間為參考對象，比較四肢末梢脈波訊號的PTT數據，在系統設定1KHz訊號取樣率的條件下，可以有效區分出四肢PTT的時間差異，將訊號取樣頻率下降至500Hz與200Hz比較四肢PTT的時間差異，在訊號取樣頻率設定在200Hz時相較於訊號取樣頻率1KHz的情形，PTT的時間差異更難被辨識出來。
經由目前測量的結果，可以總結出對於PTT的測量與計算，在訊號取樣頻率的設定上使用1KHz的訊號取樣頻率是比較好的設定，並且也驗證自製的高取樣率無線傳輸系統是可以被用在對生理訊號的測量，但是仍有許多改善空間。

關鍵字

脈波傳導時間 ； 脈率傳導速率 ； 光體積量測脈波訊號 ； 心電圖訊號 ； 無線傳輸

並列摘要

Pulse Transient Time (PTT), for the analysis of physiological signals is an important parameter, can be used to estimate the heart rate variation (HRV), blood pressure (BP) ... and other signals, So the PTT time is correct or not for the human body Physiological signal measurement and estimation has an important impact. In this paper, we discuss the influence of sympathetic nerve or other physiological phenomena, and assume that the position of the blood flowing from the heart through the position of the body and the distance length are different and the blood flow velocity is constant at the same speed, the PTT of the limb pulse conduction characteristic of the human body is measured, Because of the measurement of different locations and have a time difference, and the higher the signal sampling frequency table is the resolution of the signal the better, more effective observation.
In this study we make a wireless body network system with the hight sampling frequency and can be stabilized at 1KHz. It is expected that this wireless transmission system can be effectively applied to human physiological signal measurement. (PPG) and electrocardiogram (ECG) of the four young healthy subjects were measured and the frequency of the signal was adjusted. The pulse wave transfer time PTT under different sampling frequencies was calculated and analyzed. Thse difference in PTT between the extremities is different under the sampling frequency, and whether the difference in pulse wave transmission can be identified.
The experimental results show that the PTT time of the peripheral pulse signal of the extremities is compared with the PTT time of the left end of the heart as the reference object, and the time difference of the PTT of the limbs can be effectively distinguished under the condition of setting the sampling rate of 1 kHz signal of the system. Frequency difference to 500Hz compared with 200Hz PTT time difference, the signal sampling frequency is set at 200Hz compared to the signal sampling frequency 1KHz case, PTT time difference is more difficult to be identified.
Through the current measurement results, it can be summed up for the PTT measurement and calculation, in the signal sampling frequency setting using 1KHz signal sampling frequency is a good setting, and also verify the homemade high sampling rate wireless transmission system can be used In the measurement of physiological signals, but there are still many improvements in space.

並列關鍵字

Pulse Transit Time ； Pulse Wave Velocity ； Photo plethysmography ； Electrocardiogram ； Wireless

參考文獻

[26] “以脈波傳導特徵評估周邊動脈血管之生理訊息研究”，范智翔

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