本研究以微波共振式感測原理為基礎，提出一種基於基板整合波導之高靈敏度平面式微波感測架構，同時應用於靜態介電材料量測與動態手腕脈搏訊號偵測。在設計上，本研究以微帶線錐形漸變結構作為訊號饋入架構，並選定電場集中之 TM010 模態為主操作模態，據此提出三種感測器：Sensor A 依序整合互補式開口環形共振器、指叉電容與軸向電容延伸機制強化局部電場，並建立等效電路模型驗證電氣特性；Sensor B 利用 TM010 模態之磁牆特性演進為半模基板整合波導以縮減電路面積；Sensor C 引入耦合模態理論，以雙八角形 CSRR 之奇偶模態分裂並運用奇模高電場集中特性提升靈敏度。三種感測器均實作於印刷電路板並以標準介電基板驗證，另整合包絡檢波解調架構與 LabVIEW 平台建構非接觸式手腕脈搏量測系統。

量測結果顯示，Sensor A 實測平均感測靈敏度達 5.85%；Sensor B 維持相近效能並成功縮減 28.6% 電路面積，實測平均感測靈敏度達 5.99%；Sensor C 靈敏度則為三者最高，實測平均靈敏度達 6.51%。在手腕脈搏偵測方面，選定 Sensor A 為主要元件，經機械震動校正後，人體手腕脈搏主頻與 BIOPAC 參考系統相比，平均心率估測誤差僅為 0.35%，展示本架構於介電量測與非接觸式生理監測之可行性。

This study presents a high-sensitivity planar microwave sensing platform based on the substrate integrated waveguide (SIW), developed for both static dielectric characterization and dynamic wrist-pulse detection. Accurate dielectric characterization and non-invasive physiological monitoring are of growing importance in electronics manufacturing and wearable healthcare, yet conventional approaches to both are often constrained by bulky equipment, strict sample requirements, or susceptibility to motion and pressure artifacts. Three sensor architectures, Sensor A, Sensor B, and Sensor C, are proposed by progressively incorporating a complementary split-ring resonator (CSRR), an interdigital capacitor (IDC), an axial capacitive extension (ACE), a half-mode SIW (HMSIW) topology, and a coupled-mode dual-resonator scheme to enhance sensitivity and reduce circuit area. The TM010 mode of a circular SIW cavity was selected as the operating mode for its highly concentrated electric field, and an equivalent-circuit model was established to verify the electrical behavior of the proposed structures.

In actual fabrication, all sensors were manufactured on printed circuit boards (PCB) and validated using standard dielectric substrates spanning a wide permittivity range. Sensor A achieved a measured average sensitivity of 5.85%, Sensor B reduced the circuit area by 28.6% while retaining comparable performance, and Sensor C attained the highest measured average sensitivity of 6.51%, outperforming several recently reported microwave dielectric sensors. Sensor A was further integrated with an envelope-detection demodulation system to measure wrist-pulse vibrations, achieving a heart-rate estimation error of only 0.35% compared with a BIOPAC reference system, demonstrating the feasibility of the proposed platform for future wearable biomedical sensing applications.

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