本論文提出一全新之微波平面共振腔結構，供無壓脈帶血壓估測使用。其不僅延續振幅解調量測法之優勢，再藉由整合開口環形與互補式開口環形兩共振腔之感測區，使基於振幅法的感測表現進一步被提升，而可調陷波響應的應用，則使此表現被再次優化。雖本論文所提出之全新結構看似相當複雜，但已證明感測器之兩共振腔可獨立進行設計與分析。且基於模擬驗證之結果，本論文所提出之結構相較於典型的共振腔，品質因數將有157%以上的增加。而由穩定振動訊號的實際量測中，感測器之靈敏度的提升趨勢可被描述，而實際之提升效果，則可從振動幅度僅±3.5 µm的極微弱訊號量測結果中，訊雜比的9.34 dB提升得到證實。而血壓之估測部分，則是利用將本論文所提出之靈敏感測器，放置於頸動脈與橈動脈，量測脈搏傳輸時間的方式進行。此外本研究提出一套嚴謹之時間校正程序，使系統與電路產生之額外時間延遲低於0.1 ms。相關式之訓練結果，脈搏傳輸時間與血壓呈現高度負相關性，其相關係數至少優於−0.72。而基於此相關式之血壓估測結果也相當準確，其均方根誤差、平均絕對值偏差和平均誤差皆分別小於5.80、5.16和0.84 mmHg。此結果及意味著，微波感測技術於此全新生醫領域運用的成功，與被製程血壓監控之穿戴式裝置的潛力。

This thesis proposes a novel microwave planar resonator as a sensor for cuffless blood pressure (BP) measurement, which applies an amplitude-modulated sensing technology for sensitively detecting BP. In this study, by integrating the sensitivity areas of both the split-ring resonator and complementary split-ring resonator, the performance of amplitude-based measurement can be improved and further enhanced by including a tunable notch design. Although the proposed sensor structure is complicated, the two resonators can be analyzed and well-designed individually. Based on the simulation, a quality factor enhancement of over 157% was observed compared with typical structures. Based on a test experiment of ultra-tiny vibration, sensitivity improvements were depicted. The signal-to-noise ratio was improved by 9.34 dB under ±3.5-µm perturbation detection. For BP measurement, the proposed sensitive sensors were used to detect the pulse transit time (PTT) between two channels corresponding to sensors upon carotid and radial arteries in a noncontact approach. The time difference error between the recorded channels was calibrated. The PTT and BP showed significantly negative correlation, and the correlation coefficient was better than −0.72. Based on the log-based relationship between PTT and BP, the BP was estimated accurately. The root mean square error, mean absolute difference, and mean error of the BP prediction were less than 5.80, 5.16, and 0.84 mmHg, respectively. The results expend a new biomedical application of microwave sensors and the potential of the proposed method in ubiquitous BP measurement.

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