基於波包解調機制之非接觸式心肺檢測系統

Low-Power Non-Contact Vital Sign Detection Based On Standing-Wave Envelope Demodulation

楊佳翔(Chia-Hsiang Yang)

指導教授 ： 張盛富

國立中正大學/工學院/電機工程學系/碩士(2015年)

摘要

本論文提出基於駐波波包解調機制之低功耗非接觸式心肺檢測系統，其中說明駐波波包解調理論，並探討待測目標在不同量測位置下之解調特性。當待測目標呈週期性運動時，其間形成之駐波波包亦帶有相關週期性運動資訊，透過偵測駐波波包即可獲得待測目標位移頻率。另外針對不同量測位置所造成的量測盲點問題，提出雙狀態相位切換機制以提升量測準確度。本系統結合生理檢測、自動回波干擾消除機制與無線傳輸，整合成可配戴式心肺檢測系統。硬體包含駐波波包解調檢測雷達、微控制處理器、與無線數據傳輸模組。生理雷達偵測呼吸心跳生理訊號，以直流位準即時補償電路消除因身體晃動或環境回波造成之直流位準偏移。利用無線數據傳輸模組將其此生理訊號傳送至主控端。此卡尺寸為6.0×5.0 cm2，如半張名片般大小，方便配戴於胸前的口袋裡。功率消耗為290.4 mW。在人體靜止時並調整於最佳線性解調點時，本心肺檢測系統呼吸訊號偵測方均根誤差為0.62bpm，心跳訊號方均根誤差為1.3bpm。

關鍵字

都卜勒相移 ； 波包檢測 ； 心肺訊號 ； 駐波

並列摘要

In this thesis, a low-power non-contact vital sign detection system based on standing-wave envelope demodulation was developed. The demodulation theory of the time-varying standing-wave envelope was described, which analyzes the standing-wave characteristic in the region between the antenna and the target. Since the target is undertaking a periodic motion, the standing-wave envelope becomes a time-varying envelope and the time-varying frequency is proportional to the target vibration rate. For this fact, the target vibration rate can be obtained once the frequency of the standing-wave envelope is demodulated. The problematic detection null problem was solved by using the novel bi-state phase time-switch technique. Next, the design of system circuits and software was presented. This system consists of a vital-sign radar, real-time dc offset compensation circuit, and wireless data transmission module, which were implemented in a PCB with the badge size of 6.0×5.0 cm2, convenient for wearing. The power consumption is 290.4 mW, the root mean square error of breath rate is less than 0.62 bpm and the root mean square error of heartbeat rate is less than 1.3 bpm.

並列關鍵字

standing wave ； Doppler phase shift ； envelope detection ； vital sign

參考文獻

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