本論文針對多輸入多輸出系統(MIMO)提出在區分合法接收者和竊聽者間通道估計效能的人工雜訊的添加與設計。本研究主要利用過去提出的差異性通道估計技術(discriminatory channel estimation)中的。差異性通道估測技術目的在於最小化合法接收者的通道估計錯誤並同時將竊聽者的通道估計錯誤維持在某個水平之上。在傳送訓練訊時，透過添加與設計人工雜訊降低其對合法接收者的影響，並同時對竊聽者造成具影響力的干擾，雜訊的設計乃是根據傳送端已知的通道估測值，並同時設計人工雜訊與訓練訊號兩者的最佳能量分配，最後藉由數值模擬結果驗證所提出的人工雜訊設計效能。透過以上結果，我們將系統模型額外添加一個中繼通訊站(relay)成為一個雙向通道估測系統模型，透過以上結果我們利用同樣的人工雜訊設計輔佐我們的通道訓練過程，最後通樣藉由數值模擬結果觀察其實際效能。

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