由於光纖分碼多工技術提供有彈性的非同步傳輸技術與高容量通訊的特性，因此，非常適合應用於區域網路的架構下。在頻域振幅編碼的光分碼多工技術中有數種常見的碼型，如M-sequence codes、Hadamard-Walsh codes或是modified quadratic congruence (MQC) codes等等。在本論文中，我們提出頻域振幅編碼的光分碼多工系統，而所提出新型的編解碼裝置分別利用陣列波導光柵以及布雷格光柵來完成。首先提出兩種碼型可利用陣列波導光柵的循環特性來做為編解碼器。由於採用M-sequence codes，因此我們提出的編解碼裝置可以同時編解碼所有使用者的codewords。若使用互補式Hadamard codes，每個使用者僅需要一個陣列波導光柵就可實現互補輸入。接著，我們再提出一種新的頻域編碼的碼型且它僅需要利用少數幾個布雷格光柵串連來完成。
在此系統中，分別採用振幅鍵移及互補鍵移的方式將電信號與便宜的非同調入射光源（LED）做電光調變，然後在經由陣列波導光柵元件或者是布雷格光柵來控制寬頻入射光源的頻域振幅部分，進而達到光頻域振幅編碼的效果。而陣列波導光柵元件會將入射光源在頻域上切割成好幾個波帶chip且依據波長的不同會分佈在不同的陣列波導光柵輸出埠端。由於可利用數個布拉格光柵做為一組濾波器，因此我們可藉由有選擇性的反射方式將寬頻非同調光源在頻域上切成一系列的碼型chip。然而每個波帶chip都有各別的中心波長，這些波長每個都不同且分佈在入射光源的頻寬之中。
因此，在我們所提出這些系統架構，不僅提供消除多使用者干擾（MUI）的能力，且還能減少系統的複雜度獲得一套便宜的光分碼多工系統。

Fiber-optic CDMA techniques provide a flexible solution for asynchronous, high capacity communication, which are the most suitable application in local area networks (LAN). Several code families can be used in the SAC OCDMA systems recently, including maximal-length sequence (M-sequence) codes, Walsh-Hadamard codes, modified quadratic congruence (MQC) codes, and so on. In this thesis, optical code-division multiple-access (OCDMA) systems of spectral amplitude coding (SAC) is presented, which uses the proposed novel optical encoder/decoder based on arrayed-waveguide grating (AWG) routers and fiber Bragg gratings (FBGs). First we propose two SAC CDMA systems adopting the cyclic properties of AWG routers. By adopting the cyclic properties of M-sequence codes over AWG routers, the encoder/decoder pair can encode/decode multiple codewords simultaneously. By using complementary Walsh Hadamard (CWH) code over AWG router, each user only need an AWG router as the encoder to implement complement keying. Next, the new code family is proposed to construct based on a series of FBG for SAC OCDMA system. Due to lower weight of proposed codes, we can construct the encoder/decoder with only a few FBGs. Therefore, it is very easy to implement.
The information signal is employing either on-off keying (OOK) or complement keying with low cost incoherent sources, then AWG router or FBG is used to control the amplitude spectra of broadband incoherent optical sources. AWG routers will spectrally slice incoming broadband optical spectrum into several spectral chips are distributed over the different output ports of AWG router. FBGs are used as filters that will make a series of code chips by method of selectively reflecting to broadband incoherent optical source spectrum with information signal. Then, each wavelength chip has different central wavelength and is distributed over the spectrum of the incoming light source.
These configurations not only preserve the ability of multiple user interference (MUI) cancellation in SAC OCDMA system, but also result in a cheap system with reduced system complexity.

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