摘要
在過去的四十年來，光纖通信技術因有能力提供豐富的頻寬、高速率傳輸與適度的安全性，已被廣泛討論。而光分碼多工接取(Optical Code-Division Multiple-Access, OCDMA)技術經由特定碼字的分配下，允許多用戶使用者隨機存取光網路，在最近幾年更被受注意。不過，早期的光分碼多工接取系統在採用時域或是跳頻編碼下，其效能嚴重地遭受到多用戶使用者干擾所影響。其後，雖然有許多研究人員提出頻域振幅編碼(Spectral Amplitude Coding, SAC)光分碼多工接取系統，在所設計的碼族有固定的同相交相關(In-phase Cross-correlation, IPCC)值下去減輕這項問題。然而，以往的頻域振幅編碼光分碼多工接取系統不論在效能或是在碼長之選擇均有不足之處。 在本篇論文中，我們將發展數種新穎的碼族與架構以作為次世代光纖網路的應用。首先，我們提出兩種新碼族，名為延伸式完美差異碼與延伸式M序列碼的碼族。應用這些碼族，我們建構與分析簡潔頻域振幅編碼光分碼多工接取被動光網路(Passive Optical Network, PON)。第二部分，我們研究新穎的二維頻域/空域的延伸式M序列碼/延伸式完美差異碼的碼族，這是鑑於延伸式M序列碼與延伸式完美差異碼的碼族所建構而成，並設計對應的系統架構，以便容納更多同時間使用者和降低介於中繼站與光網路單元間的光纖數量。第三部份，我們集中我們的專注力在一種重要的方式，來建構分割式局部質數碼的碼族具有低的同相交相關值、優良的碼平衡與彈性碼長等特性，適合於高速傳輸的頻域振幅編碼光分碼多工接取被動光網路下的應用。此碼族是從眾所皆知的質數碼與分割方式所衍生出的。在最後一部分，超完美差異碼是被提出並應用在簡潔頻域振幅編碼光分碼多工接取被動光網路上。所提出的被動光網路不僅可容納大量的同時間使用者而且兼具簡潔的架構與適度的安全性。
並列摘要
In the past four decades, the optical fiber communication techniques were widely studied because they are capable of providing abundant bandwidth, high-rate transmission, and moderate security. Among them, the optical code-division multiple-access (OCDMA) technique, which has the potential advantage of allowing multiple users to randomly access optical network through the assignment of unique codewords, attracts a lot of attention in recent years. Nevertheless, the performance of early OCDMA systems is seriously suffered from the influence of multi-user interference (MUI) when the time-spreading or frequency-hopping schemes are used. Afterward, to mitigate the problem, the researchers proposed the spectral amplitude coding (SAC) optical CDMA systems when designed code families have a fixed value of in-phase cross-correlation (IPCC). However, the previous SAC optical CDMA systems are limited in performance or in the code length selection. In the dissertation, we develop several newly code families and architectures which can be applied to the next-generation optical networks. First of all, we present two new code families, named the extended perfect difference (EPD) code and extended M-sequence (EMS) code families. Using these codes, we construct and analyze the compact SAC optical CDMA passive optical networks (PONs). Second, we study the two dimensional (2-D) Spectral/Spatial (SS) EMS/EPD code family based on EMS code and EPD code families. We also design the corresponding system architecture in order to accommodate more simultaneous users and reduce the number of optical fibers between the remote node (RN) and the optical network units (ONUs). Third, we focus on a significant approach to construct the partitioned partial prime (PPP) code family, which has the property of low IPCC value, good code balance, and flexible code length, suitable for high-rate SAC optical CDMA PONs applications. They are derived from the well-known prime codes (PCs) and a manner of partitioning technique. Finally, the super perfect difference (SPD) code is proposed and used in compact SAC optical CDMA PONs. The proposed PON not only can accommodate a large number of simultaneous users but also has compact configuration with moderate security.
參考文獻
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