Optical Access Network based on OCDMA Systems : Transmission and Security Performance

multiple access (OCDMA), modified quadratic congruence (MQC). Abstract— In this article we aim to investigate the theoretical and simulation analysis of the next-generation optical access network based on optical code division multiple access (OCDMA) technique. Hence, incorporating this technique with passive optical network (PON) will enable the system to support higher bandwidth compared to the standard PON. In this paper, an overview of optical OCDMA features such as increasing system capacity, physical layer network security, and improving the system performance were presented. The transmission performance of PON network based on OCDMA technique has been theoretically investigated using balanced detection scheme when modified quadratic congruence (MQC) codes were assigned as a signature sequence codes for the subscribers. Consequently, the effects of the contributed noises have been considered. These noises are phase-induced intensity noise (PIIN), shot noise and thermal noises. In addition, the system of 25 subscribers was simulated with MQC codes at the C band for the upstream signal with channel spacing 50 GHz. In addition, the system was simulated using modified prime code for multi premises network.Variation in the results was studied when fiber length and data rate were varied and different transmission power was applied. The system shows good results in terms of the bit error rate (BER), and suppression of multiple access interference (MAI). Furthermore, the security performance of the coding technique, at the physical layer, has been investigated based on the code properties for the MQC. As the code size is increased, both the complexity for the eavesdropper to detect high spectral chip pulse signal to noise ratio (SNR) and the system capacity are increased.