本研究旨在利用外差混頻的技術，抑制半導體雷射在光回饋機制下產生的混沌態之時間延遲特徵，以及透過在頻寬利用率上的優勢，將此技術應用在多通道雷達的開發。藉由微波混頻器，將混沌訊號與外加的單頻波訊號進行混頻，混頻之後的混沌訊號其時間延遲特徵將隨著不同的混頻頻率而有不同的抑制效果。本研究提出兩種混頻的方式，操作在適當的混頻頻率，能有效的抑制時間延遲特徵，最佳的抑制效果可以消除70.85%的整體時間延遲特徵。在多通道雷達開發的部分，我們首先研究外差混頻的技術對於混沌訊號頻寬利用率的影響，藉由改變混頻頻率，觀察不同混頻頻率的外差混沌訊號兩者之間的相關程度，實驗結果顯示，當混頻頻率相差0.2MHz，輸出的外差混沌訊號彼此相關性極低，因此，在混沌頻譜上，只要相隔0.2MHz的頻率就能透過外差混頻的方式，同時輸出不同頻譜範圍的混沌訊號，有效的增加了頻寬的利用率。我們透過此技術在頻寬利用率上的優勢，發展出一套多通道雷達系統，當此系統操作在適當的混頻頻率，就能透過單一的雷射光源同時產生多個彼此正交的雷達訊號源。

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