近年來，分碼多重進接技術(Code Division Multiple Access, CDMA)應用於無線射頻(Radio Frequency, RF)通訊系統已成為最熱門的話題。此外，其高速及高頻寬的訊號處理特性，將展頻技術延展到光區域網路(Fiber-Optic Local Area Network)的概念也在之前被驗證成功。在一個CDMA系統裡面，接收器必須在其他使用者傳送資料的干擾情形下偵測出與其接收器相搭配的傳送器送出的特徵碼；因此每個使用者都擁有自己的特徵碼，藉由區分特徵碼來來存取網路上的資料。為了增加系統上使用者的上線數目，則必須降低在接收端因訊號碰撞所造成的干擾現象。
二維碼(2-Dimensional Code)的出現則是為了改善先前發展的一維碼的缺點，並保有了原先在一維碼上良好的相關特性(Correlation Property)；在提供相同的使用者數目時，與一維碼相比較，二維碼擁有較短的編碼長度，除此之外二維碼在其他方面亦有勝過一維碼句的效能表現。在此論文中，我們利用之前提出的一維最長序列碼句 (Maximal-Length Sequence, M-sequence) 經過並列化的修改，再結合時域上的展頻加上波長跳頻觀念來發展出一個新式的混合編碼系統.。我們也將這一個新式的二維編碼應用於同步與非同步之光分碼多工系統上，分析其效能並與先前已被提出的質數跳頻二維編碼系統做比較。在這個提出混合編碼系統中，它擁有良好的相關特性，亦能以較易實現的低複雜度二維CDMA系統來提供更多的使用者數目。

CDMA technology has been popular topical subject applied in the RF domain communication system. And, a spread spectrum fiber-optic local network utilizing high-bandwidth optical processing was demonstrated previously. In CDMA systems a receiver has to detect a signature sequence in the presence of interferences in the form of transmissions from other users. So each user has its own signature code to access the network. To increase the simultaneous users in the system, the collisions in the receiver must to be lower down. 2-D codes have the advantages of maintaining good correlation properties in 1-D codes to reduce collisions, smaller code length then 1-D codes with supporting the same number of simultaneous users, and even better performance than 1-D codes in many other ways. Here, we combine previously discussed 1-D maximal-length sequence (M-sequence) codes with time spreading and wavelength hopping techniques to develop a new hybrid system. We also apply the new developed hybrid code sequences into the synchronous and asynchronous OCDMA systems. In order to analyze the performance of the hybrid system, we compare the performance with the proposed prime-hop system. In this proposed hybrid system, it has the advantages of good correlation properties for asynchronous system and more simultaneous users with simpler and lower cost configuration in 2-D systems.

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