本論文探討在多重路徑環境下，利用陣列接收機所接收之訊號，辨識直視路徑訊號所對應之指向天線方法，以改善訊源誤判問題。
本論文使用模稜函數，估測各多重路徑與直視路徑之相對延遲時間。此外，採用正規化最小均方演算法估測多重路徑通道模型，包含延遲時間與通道增益，以驗證模稜函數所估測之時間延遲。
論文所提方法比對所得之通道估測，與各指向天線與全向監視天線之互相關計算結果，以判斷辨識直視路徑入射方向所對應之指向天線。利用此資訊，可避免來自多重路徑方向之訊源誤判。
論文以擷取之雷達訊號及抽頭延遲線通道模型進行軟體模擬及硬體實驗，以探討演算法之可行性及未來改進方向。

This thesis investigates a method that identifies a directional antenna corresponding to the line of sight signal source based on radar array received signals in a multipath propagation environment. The method can improve false decision of signal direction problem.
This work uses an ambiguity function to estimate the relative time delay between each multipath and the line of sight. Additionally, a normalized least mean square algorithm that identifies the multipath channel model including the time delays and gains are also used to verify the estimation results of the ambiguity function.
The proposed method compares the channel estimation and the cross-correlation results of each directional antenna and an omni-directional surveillance antenna to determine the incident line-of-sight and multipath signals corresponding directional antennas. With such information, false alarms in the directions associated with multipath can be avoided.
Computer simulations and experiments are performed to verify the feasibility of the proposed method, where a set of recorded radar signals are used as sources and a tap-delay-line model is adopted to simulate a multipath channel. Future work of improving the proposed method is also discussed based on the verification.

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