AbstractsComputer Science

In this thesis few new code sets and a multi-user interference (MUI) cancellation scheme have been proposed for Optical Code Division Multiple Access (OCDMA) systems, which can be employed in the next generation of global communication networks to enhance their existing systems’ performance dramatically. The initial evaluation of the proposed code sets shows that their implementation improves the performance, decreases the BER and increases security considerably. Also the proposed MUI cancellation scheme totally removes all the cross-talk and interference between the active users within the network. These novel schemes and codes can be easily implemented in the optical packet switched networks. Optical switching has the ability of bandwidth manipulation at the wavelength level (e.g. with optical circuit/packet/burst switching); the capability to accommodate a wide range of traffic distributions, and also to make dynamic resource reservations possible. This thesis first gives a brief overview of co-channel interference reduction in OCDMA networks, then proposes two novel code sets, Uniform Cross-Correlation Modified Prime Code (UC-MPC) and Transposed UC-MPC (T-UCMPC), along with their evaluation and analysis in various systems, including IP routing over an OCDMA network. Thereafter, the new MUI cancellation scheme is proposed and then the proposed code sets and the MUI cancellation scheme are implemented and analysed in a laboratory-based experimental test bed. Finally the conclusion of this research is discussed.