本論文基於放大後前送 (Amplify-and-Forward, AF) 的雙向傳輸中繼網路 (Two-Way Relay Networks, TWRN) 系統架構，在多路徑傳輸的通道環境下，針對半盲式通道估測法 (Semi-Blind Channel Estimator) 提出預編碼機制 (Precoding Scheme)，該系統架構考慮兩終端節點 (Terminals) 透過多中繼節點 (Multi-Relays) 相互交換訊息。預編碼機制主要是終端節點用來區分接收到來至多中繼節點的訊號，該機制並可降低半盲式通道估測器的計算複雜度 (Computation Complexity)。
中繼節點藉由非冗餘 (Non-Redundant) 線性預編碼機制，以半盲式通道估測法估測直進路徑 (Direct Link) 以及串接 (Cascaded) 等效路徑的通道脈衝響應 (Channel Impulse Response, CIR)。首先，半盲式通道估測器利用少許的訓練符元 (Training Symbols) 以最小平方 (Least Square, LS) 估測法估測兩終端節點間直進路徑的通道脈衝響應。其次，終端節點透過接收訊號之二階統計(Second-Order Statistics, SOS)特性取得串接等效路徑的通道脈衝響應。
總結，我們所提出的機制對整體系統而言，可以有效降低系統的計算複雜度並提高頻譜使用效益。模擬結果亦證實本篇論文所提出機制的有效性。

In this thesis, we proposed a precoding scheme for semi-blind channel estimation in amplify-and-forward (AF) multipath two-way relay networks (TWRN), where two terminals exchange their information through multi-relays. The precoding scheme, which diminishes computational complexity of semi-blind channel estimator, is used to distinguish received signal at both terminals from multi-relays.
By applying a non-redundant linear precoding scheme at multi-relays, we proposed a semi-blind channel estimation to estimate the channel impulse response (CIR) of direct link and the cascaded source-relay-terminal links. Firstly, semi-blind channel estimation adopts least-square (LS) estimation to find the CIR of direct link between both terminals using a smaller number of training symbols. Secondly, the CIR of the cascaded source-relay-terminal links are obtained through second-order statistics (SOS) of received signals at both terminals.
Consequently, the proposed scheme can effectively reduce the computational complexity and enhance the spectral efficiency in overall system. Simulation results corroborate the effectiveness of the proposed scheme.

論文審定書 i
誌謝 ii
中文摘要 iii
Abstract iv
目錄 v
圖次 vii
第一章 導論 1
1.1 研究背景 1
1.2 研究動機 4
1.3 論文架構 6
第二章 系統模型 7
2.1 雙向傳輸中繼網路 8
第三章 所提出之預編碼結構 14
3.1 預編碼矩陣 14
3.2 編碼矩陣與通道矩陣結合 17
第四章 半盲式通道估測 22
4.1 直進路徑通道估測 23
4.2 串接路徑通道估測 24
4.3 獨立且平均值為零的圓形對稱高斯隨機向量之特性 28
4.4 總結 34
第五章 模擬結果 35
第六章 結論 39
參考文獻 40
中英對照表 46
縮寫對照表 51

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