本論文是採用Wi-Fi訊號作為都卜勒雷達系統的發射訊號源，並結合IQ正交解調的接收機架構，進行同時人體生理監測與測距的實驗。由於Wi-Fi訊號含有振幅調制(AM Modulation)以及相位調制(PM Modulation)成分，導致系統的感測性能下降，為了改善雷達性能，經由本實驗室提出的注入鎖定技術以及雙通道雜訊抵銷法來抑制Wi-Fi訊號的振幅和相位調制，使都卜勒訊號品質提升，進而量測到呼吸及心跳訊號。
為了使Wi-Fi雷達能夠測距，本論文利用頻移鍵控(FSK)的測距觀念提出藉由RF開關切換兩不同載波頻率的Wi-Fi訊號搭配校正電路延遲的方法，得到正確的相位差再利用數位訊號處理的方式，將相位差轉換為距離資訊。接著為了實現多人同時生理訊號監測與測距，使用1T6R一維數位波束成型架構，並利用雙通道雜訊抵銷法來抵銷Wi-Fi調制以及搭配FSK測距技術，不僅可以清楚分辨各目標所在的方位角還能監測到個別目標的呼吸、心跳以及距離資訊。

The aim of this study is to develop a passive Doppler radar based on an injection-locked quadrature receiver architecture. The system uses a Wi-Fi access point module as a transmission signal source to detect human vital signs and their distances simultaneously. Due to the presence of amplitude modulation (AM) and phase modulation (PM) components in Wi-Fi signals, the sensing performance of the system is degraded. To improve radar performance, the injection locking technique and dual-channel noise cancellation method proposed by our laboratory are employed to suppress both amplitude and phase modulations, thereby enhancing the quality of Doppler signals and enabling the measurement of respiratory and heartbeat signals.
In order to enable distance measurement with Wi-Fi radar, this study introduces a method based on the concept of frequency-shift keying (FSK) to switch between two different carrier frequencies of Wi-Fi signals using RF switches with compensation for circuit delays. By obtaining the correct phase difference and utilizing digital processing techniques, the phase difference can be converted into distance information accurately. Furthermore, to achieve simultaneous measurements of multiple individuals' vital signs and distances, a 1T6R one-dimensional digital beamforming architecture is utilized. The dual-channel noise cancellation method is employed to suppress Wi-Fi modulation noises, and in conjunction with FSK ranging technology, it allows for angular differentiation between various targets, as well as the simultaneous monitoring of their respiration, heartbeat, and distance information.

論文審定書 i
誌謝 ii
摘要 iii
Abstract iv
目錄 v
圖目錄 vii
表目錄 x
第一章 序論 1
1.1 研究背景與動機 1
1.2 雷達簡介與應用 2
1.2.1 主動雷達 2
1.2.2 通訊通道感測技術 5
1.2.3 被動雷達 6
1.2.4 注入鎖定式被動雷達(ILQR) 7
1.3 波束成型簡介 8
1.4 章節規劃 9
第二章 生理監測與定位之Wi-Fi感測技術 11
2.1 前言 11
2.2注入牽引抵銷技術 11
2.2.1 初代注入鎖定被動雷達 11
2.2.2注入牽引抵銷機制 14
2.3直流準位偏移校正(DC-Offsets Removal) 16
2.3.1內部電路不完美貢獻之直流準位偏移 16
2.3.2外部因素貢獻之直流準位偏移 17
2.4 頻移鍵控(FSK)技術 20
2.4.1 前言 20
2.4.2 距離追蹤理論 21
2.4.3 電路系統延遲 23
2.5 數位波束成型技術(Digital Beamforming) 24
2.6 系統實現 27
2.6.1測距雷達實驗 28
2.6.2 多人定位與生理監測實驗 30
第三章 感測實驗與結果討論 33
3.1 擺動金屬板偵測實驗 33
3.1.1 測距實驗 33
3.1.2 靈敏度實驗 39
3.1.3 抗干擾實驗 40
3.2 多人定位與生理監測實驗 46
3.2.1 陣列天線設計 46
3.2.2 實驗結果 48
第四章 結論 55
參考文獻 56

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