Improving network scalability and data security of incoherent OCDMA systems by employing ultrafast all-optical signal processing techniques

摘要

Optical code-division multiple access (OCDMA) is a data multiplexing technique which can support bursty traffic, variable data rates and can deliver superior network scalability. However, the performance of OCDMA systems can be severely limited by multiple access interference (MAI) and interferometric noise (IN) which will gradually degrade system performance with the growing number of simultaneous users. The effect is called soft blocking. On the other hand the soft blocking property can be used to trade the system performance (bit error rate, BER) against the existing number of simultaneous users present on the OCDMA network. We have investigated the use of ultra fast all-optical signal processing to mitigate the deleterious effects of both MAI and IN on the BER under different network conditions. In addition, to address network security, spectral efficiency, and to improve OCDMA system scalability, different approaches and techniques involving optical and all-optical signal processing were investigated and demonstrated.