利用光可於單模光纖中以兩個互相正交極化狀態傳輸的特性，我們提出一個架構於極化分光器(Polarization beam splitter, PBS)與陣列波導光柵 (Arrayed-waveguide grating, AWG) 之光分碼多重存取 (Optical code-division multiple-access, OCDMA) 編/解碼裝置，利用極化分集(Polarization diversity)的概念以實現非同調光源之頻域極化編碼 (Spectral-polarization coding, SPC)。系統使用者的簽章碼 (Signature code)是以Walsh-Hadamard矩陣來建構。且根據傳送位元的不同 (1 or 0)，指派的簽章碼將搭配一組相反的正交極化狀態。
　　在解碼端，由於所接收到的訊號包含不同波長的極化狀態資訊，因此先以AWG取出相對應於編碼機制的波長，再以PBS分離正交的極化狀態，最後以雙重平衡差異檢測來判別使用者所傳送的資訊。由於Walsh-Hadamard矩陣為正交矩陣，使得多重擷取干擾 (Multiple access interference, MAI) 理論上可被完全消除。再者，SPC機制相較於同樣以Walsh-Hadamard碼架構之頻域振幅編碼系統，更能有效的抑制相位引致強度雜訊 (Phase-induced intensity noise, PIIN)，提高其訊號雜訊比。因此同時使用者的數目也會相對的提高。
　　總結來說，在我們所提出的系統架構中，雖然嵌入極化分集的技術，但於接收端無需任何解極化裝置即可獲得較佳的系統性能。

　　Utilizing the property that the light can transmit with two mutually orthogonal states of polarization (SOPs) in single mode fibers, we propose the optical code-division multiple-access (OCDMA) encoder/decoder (codec) structure based on polarization beam splitters (PBSs) and arrayed waveguide gratings (AWGs) and utilize the concept of polarization diversity to implement spectral-polarization coding (SPC) with incoherent optical source. The signature code of users in the system is addressed by the Walsh-Hadamard matrix. And according to different transmitted bits (1 or 0), the specific signature code would accompany with a set of contrary orthogonal SOPs.
　　At the decoder, the received signal, which includes the SOP information to each wavelength, is took out the corresponding wavelengths matched with encoding scheme then split into two orthogonal SOPs with PBS. Finally, the transmitted signals from users are determined by the double balance-difference detection. Due to the Walsh-Hadamard matrix is an orthogonal matrix, the multiple access interference (MAI) is eliminated in theory. Moreover, the SPC scheme is superior to the spectral-amplitude coding system with Walsh-Hadamard code and results in suppressing effectively phase-induced intensity noise (PIIN) and boosting the signal-to-noise ratio (SNR). Hence, the number of simultaneous active users could be also upgrade.
　　To sum up, although embedded polarization diversity technique over AWG-based codec in OCDMA network, the performance would be improved without any depolarization device.

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