Analysis of Optical Code Division Multiple Access Passive Networks for Different Encoder Delay Elements

One of the most important core technologies in the development of optical code division multiple access (OCDMA) local area networks is the optical encoder/decoder embodiment technology which codes information to fixed patterns at the transmitting side and decodes information at the receiving side. The selection of optimized encoding method for network composition is necessary to accommodate a maximum number of subscribers that have simultaneous access over the local area network and the bandwidth of subscriber services available on it. When composing this encoder/decoder optically, passive elements are exclusively used, if possible, so as to make the composition method simple and economical. In this paper we present an analysis of OCDMA passive communication networks focusing on the modeling of optical encoder/decoder blocks for different types of delay elements. The main objective of the paper is to study the performance of these networks including the effect of the passive encoder/decoder parameters such as splitter and optical delay line losses. Different types of delay lines are proposed including optical fibers and fiber Bragg gratings (FBG) as delay elements for the selection of the optical delay line which achieves a better performance. A statistical model of an OCDMA network has been developed and used for this study, including the effect of different passive encoder/decoder parameters, multiple access interference and noise