本論文提出了一個使用延遲與自我注入鎖定 (Delay- and Self-Injection-Locked, DSIL) 技術的數位低中頻毫米波生命體徵雷達，旨在提升射頻前端模組的頻段至毫米波頻段，並驗證其功能性。利用數位延遲電路 (Digital Delay Line) 與比例積分控制器 (Proportional-Integral Controller, PI Controller) 即時補償人體位移所造成的相位偏移，使自我注入鎖定迴路的相位保持在最佳感測點。此技術有效解決了雷達的零點問題，顯著提升了雷達的擺幅靈敏度與線性度。
在實驗中，此雷達系統的線性度在金屬板等速移動下的擺幅靈敏度可達到20μm，在量測固定位置金屬板的擺幅靈敏度可以達到理論的極限值3.16μm。此外，雷達系統整合鏡像拒絕電路與雜波抵消電路，並以數位電路實現在現場可程式化邏輯閘陣列 (Field Programmable Gate Array, FPGA) 內，有效提升了鏡像拒絕效能。
訊號處理結合集合經驗模態分解方法 (Ensemble Empirical Mode Decomposition, EEMD) 還原心臟訊號波形，並利用峰值檢測提取心跳間隔 (interbeat interval, IBI) 進行心率變異性 (Heart Rate Variability, HRV) 分析，與參考的ECG訊號進行比較。實驗結果顯示，Bland-Altman圖表明兩種測量方式之間具有良好一致性。時域指標分析顯示心率整體可變性和短期變化高度相關，頻域指標分析清楚顯示靜態下的自主神經系統狀態及外部刺激下的反應動態。
本研究證明了此雷達系統在生理訊號量測的卓越性能，為未來在醫療監測與人體生理參數測量中的應用提供了重要技術基礎。

This thesis proposes a digital low-IF millimeter-wave vital sign radar using Delay- and Self-Injection-Locked (DSIL) technology, aiming to elevate the frequency band of the RF front-end module to the millimeter-wave range and verify its functionality. By utilizing a digital delay circuits and a proportional-integral (PI) controllers, it compensates for the phase shift caused by human movement in real-time, maintaining the phase of the self-injection locked (SIL) loop at the optimal sensing point. This technology effectively solves the radar's null-point problem and significantly enhances the radar's amplitude sensitivity and linearity.
In experiments, the linearity of this radar system achieves a vibration sensitivity of 20 μm for a constant-velocity moving metal plate. The vibration sensitivity for measuring a metal plate at a fixed position can reach the theoretical limit of 3.16μm. Additionally, the radar system integrates image rejection and clutter cancellation circuits, implemented digitally on a field-programmable gate array (FPGA), effectively enhancing the radar's image rejection performance.
The subsequent signal processing combines the Ensemble Empirical Mode Decomposition (EEMD) method to restore the cardiac signal waveform and uses peak detection to extract the interbeat interval (IBI) for heart rate variability (HRV) analysis, compared with the reference ECG signal. Experimental results show that the Bland-Altman plot indicates good consistency between the two measurement methods. Time-domain indicators analysis reveals a high correlation between overall heart rate variability and short-term changes, while frequency-domain indicators analysis clearly shows the autonomic nervous system state in a static condition and provides insights into the dynamic changes in response to stress or other external stimuli.
This study demonstrates the excellent performance of this radar system in vital signal measurement, providing a crucial technological foundation for future applications in medical monitoring and human physiological parameter measurement.

論文審定書 i
致謝 ii
摘要 iii
Abstract iv
目錄 v
圖次 vii
表次 ix
第一章 緒論 1
1-1 研究背景與動機 1
1-2 都卜勒雷達介紹 2
1-3 自我注入鎖定雷達介紹 5
1-4 章節規劃 8
第二章 系統架構與原理 9
2-1 毫米波射頻前端與雷達系統實現 9
2-2 DSIL數位低中頻雷達 11
2-3 訊號處理 15
2-3-1 MATLAB訊號處理流程 15
2-3-1-1集合經驗模態分解 (EEMD) 方法 15
2-3-1-2 自相關方法 18
2-3-2根據時域和頻域的心率變異性 (HRV) 指標 21
2-3-2-1時域指標 22
2-3-2-2頻域指標 23
2-3-3 Bland-Altman圖 25
第三章 感測實驗與結果 28
3-1移動金屬板偵測實驗 28
3-1-1雜波消除效果量測 28
3-1-2靈敏度量測 33
3-1-3線性度量測 34
3-1-4與先前研究[37][56]的性能比較 38
3-2人體生理感測實驗 38
3-2-1生理訊號量測 39
3-2-2緩慢移動下生理訊號量測 42
3-2-3與先前研究[14] [47]的結果比較 46
第四章 結論與未來展望 52
參考文獻 53

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