在這篇論文中，我們提出一個實現光分碼多工系統的頻域編解碼裝置並以實驗驗證之。此編解碼裝置是利用布雷格光柵設計而成。基於我們所發展出來的調變與檢測技巧利用平衡檢測器對近乎正交碼作相關函數的相減，我們所建議的布雷格光柵編解碼器，其架構卻與以往被發表的極為不同。我們在此是利用布雷格光柵其穿透頻譜的特性，來架構我們的編解碼器。然而，它卻提供了幾個重要的優點。首先，在不採用迴光器的架構之下，系統實現成本得以降低。其次，我們的架構可以解決路遊時間效應的問題。此外，我們還能些微地減少功率損耗問題。我們的實驗平台是由兩個主動的發射編碼器與三個接收解碼器所構成。對匹配與不匹配的情況同時作驗證。在本實驗中，為了考量多重擷取干擾可能由非平坦光源所造成，因此我們盡量將頻譜切割在寬頻光源其較平坦的中心區域，以做為部份的補償。量測結果證明我們所提議的方法是成功並且可實行的。

　　In this thesis, a realization technique of optical CDMA spectral-coding with fiber-Bragg-grating (FBG) -based codecs was proposed and experimentally demonstrated. Based on the modulation and detection principles that we have developed -- correlation subtractions of nearly orthogonal codes with balanced photo-detectors, this proposed FBG encoder/decoder configuration is much different from those published in the past. We introduce the transmissive spectral characteristics of FBGs to construct our FBG encoder/decoder. Instead, it provides several important advantages. First, the cost is lowered due to our circulator-free architecture. Second, the round-trip time problem is resolved. Besides, we also can reduce the power loss issue slightly. The testbed consists of two active encoders and three decoders. Both matched and unmatched cases are demonstrated. In order to counter the multiple-access-interference (MAI) effects caused by non-flattened optical sources, the spectral amplitude is sliced in the more flattened central region of broadband optical sources for partial compensation in our experiment. Our measurements verify that our proposed scheme is successful and practicable.

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