Enhanced bandwidth utilization in optical CDMA-WDMA-DWDMA networks

The ever-increasing demand on bandwidth for high-speed network applications such as Internet requires increased throughput, parallelism and better network topologies. Among the various throughput enhancement techniques, Code Division Multiple Access (CDMA), Wavelength Division Multiple Access (WDMA) and Dense Wavelength Division Multiple Access (DWDMA) have shown remarkable promise for high-speed network applications. CDMA is a method for sharing the bandwidth of an optical fiber, which uses code sequences as traffic channels. WDMA is a method where multiple channels share a single wavelength in a fiber, and DWDMA is a technique that combines and transmits multiple signals simultaneously at different wavelengths through the same fiber. Simulation results obtained using MATLAB and OPNET software packages show that DWDMA outperforms WDMA. This work also shows that it is possible to improve the performance of random access CDMA by using various antenna models in a wireless network. Based on our results, we concluded that the demands of high-speed networking application could be met by developing a system that dynamically switches between WDMA, CDMA, and DWDMA techniques for a given application.