本論文提出以Wi-Fi為訊號源結合轉頻技術結與注入鎖定架構的被動式雷達系統。透過此系統，可達到使用者在進行無線Wi-Fi傳輸的時，連線的穩定度不會受到系統的影響。此外，本文另結合FSK的操作模式，使其能夠獲得目標的距離。由於Wi-Fi訊號自身的振幅調制和相位調制，導致解調後的基頻訊號較難以獲得到微弱的心跳，因此本文另外結合雙通道抵銷技術，有效提升基頻訊號的訊噪比，從而能夠準確量測人體的生理訊號。
另外本文也運用MIMO系統，結合分時多工(Time-Division Multiplexing, TDM)的方式，使雷達更進一步具有垂直以及水平方位的解析度，透過數位波束成型的演算法，達成對目標的成像應用。

This paper proposes a passive radar system that utilizes Wi-Fi as a signal source and combines frequency-conversion technology with an injection-locked architecture. This system ensures that the stability of the user's wireless connection remains unaffected during data transmission. Additionally, the system incorporates FSK operation mode, enabling it to accurately determine the distance to the target. Due to the inherent amplitude and phase modulation in Wi-Fi signals, the demodulated baseband signal may struggle to capture weak heartbeat signals. To address this, the paper introduces dual-channel cancellation technology, significantly improving the signal-to-noise ratio (SNR) of the baseband signal, thereby allowing for precise vital sign detection.
Furthermore, this paper employs a MIMO system in conjunction with Time-Division Multiplexing (TDM) mechanism, which obtains the radar’s vertical and horizontal resolution. By utilizing digital beamforming algorithms, the system is capable of achieving imaging applications for the target.

論文審定書 i
摘要 iii
Abstract iv
目錄 v
圖次 vii
表次 x
第一章 序論 1
1.1 研究背景與動機 1
1.2 雷達種類介紹與應用 2
1.2.1主動雷達 2
1.2.2 被動雷達 5
1.2.3 通道狀態訊息感測 6
1.2.4 注入鎖定式被動雷達(ILQR) 7
1.3 相位陣列 8
1.4 雷達成像 8
1.5 章節規劃 9
第二章 轉頻注入鎖定雷達 10
2.1 前言 10
2.1本地振盪洩漏問題 10
2.2 Wi-Fi感測原理及注入牽引抵銷技術 11
2.3 直流準位偏移校正(DC-Offsets Removal) 13
2.3.1 直流準位偏移來源 13
2.3.2 校正方式 14
2.4 轉頻CW感測模式 16
2.4.1 系統架構 16
2.4.2 靈敏度測試 19
2.4.3 生理感測 23
2.5 轉頻結合FSK測距模式 26
2.5.1 測距原理 26
2.5.2系統架構 26
2.5.3 金屬板測距驗證 30
2.5.4 人體測距與生理感測 34
第三章 人體成像 40
3.1 前言 40
3.2 陣列天線設計 40
3.3 二維成像 41
3.3.1 訊號處理與校正 41
3.3.2 系統架構 45
3.3.3 角度解析度 48
3.3.4 人體成像與定位 50
第四章 結論 55
參考文獻 56

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