在這篇論文中，我們提出一個非同步光訊分碼多工網路，串接在布雷格光纖光柵與陣列波導光柵的架構，這可以提高系統使用者的數目。我們利用光譜作編碼來完成光纖分碼多工網路，並運用最大長度碼的特性，使我們可以在接收端以平衡檢測來得到使用者的資訊。

為了達到編碼的目的，布雷格光纖光柵需以串連方式來架構光纖分碼多工系統，然而，當使用者數目增加，所需要的最大長度碼變大，光纖光柵所佔的長度也變長，這使得原本可以忽略的一些非理想化特性變的不可忽視。為了增加使用者數目，而又要降低非理想特性的影響，我們採取另一方法，將幾個使用者視為一個群，在中間增加了一階陣列波導光柵的架構，利用陣列波導光柵分波多工的特性搭配延遲線來對經過光纖光柵編碼過的一個群的使用者訊號再一次編碼。

而在另一方面，延遲線在陣列波導光柵分配的特性會影響系統的效能，不同的分配方式，亦即是不同的碼會使干擾群的訊號分布在不同的時間上。所以找尋較好的碼，能使其他使用者的干擾降低，改善系統效能，將是未來努力的目標。

In this thesis, an asynchronous optical code-division multiple-access (CDMA) network, which is based on cascaded fiber Bragg grating (FBG) and arrayed waveguide grating (AWG) devices, is proposed, and it allows more users to access the network. In this system, an optical spectrally encoding scheme is devised for CDMA networks, and we use the maximal-length sequence (M-sequence) to perform balanced detection to acquire information of users at the receiver.

The multiple FBGs are cascaded in the system to encode the signals. However, when the number of users increases, length of M-sequence becomes longer and the length of total FBGs required becomes longer too. Therefore, some non-ideal properties, which can be neglected at the short-length code system, become serious. Another alternative is to treat some users as a group, insert a stage of AWG structure, and encode the signal of group by the AWG combined with delay lines.

On the other hand, delay characteristic will affect the performance. Different distribution causes the signals of interference group spread on different time slot. Seeking better code family to reduce the interference of other users will be our future improvement.

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