OCDMA是未來高速全光網通信網絡的備選方案之一，是目前通信研究領域的熱點。其中光編解碼器是OCDMA系統中的關鍵技術。研究表明， LPG以其插入損耗小、波長編碼、無后向散射、不受電磁干擾、兼容于光纖等優點，在光纖通信和傳感領域均有重要的應用價值。基于長周期光纖光柵的各種優勢，針對OCDMA編解碼器的設計，通過optisystem及optigrating應用軟件對長周期光纖光柵的耦合模式進行仿真，并通過搭建OCDMA系統模型，得出編解碼結果。驗證了用長周期光纖光柵做OCDMA系統的編解碼器的可行性。

　　Abstract:

　　OCDMA is one of the schemes of the future high-speed optical communication network，and it is also a research hotspot.In OCDMA，codec is the key technology.Research shows that LPG have advantages:such as low insertion loss，wavelength coding，no back scattering，unaffected by electromagnetic interference，compatible with fiber etc.So it has an important application value in optical fiber communication and sensing technology.Based on this advantage，this paper discussed the codec technology and simulated the coupling model of long period fiber grating with the optisystem and optigrating application software.By constructing OCDMA system model，the decoding results were concluded，which verified the feasibility of using long period fiber grating as the codec of OCDMA system.