Optical packet networking using optical time division multiplexing.

Growing demands for capacity have stimulated the development of high-speed optical shared media networks. At present, most research on optical networking has concentrated on wavelength-division multiplexing (WDM). Optical time-division multiplexing (OTDM), which offers advantages over WDM networks, is considered as an alternative to WDM for future networks proving a single stream data rates of 100 Gb/s using a single wavelength. In such systems all optical routers, which overcome the bottleneck of optoelectronic conversion, play an important role. This thesis concentrates on the modelling and simulation of a novel optical router, which uses two terahertz optical asymmetric demultiplexers (TOAD) as the routing element for OTDM systems.In this work, the author has developed a mathematical model of an all optical router based on TOADs. The model architecture is based on a system, which has as its input an OTDM packet containing header and payload information. The model simulates extraction of header information, using one TOAD, from the data stream, which is subsequently used to make a routing decision. The payload information is routed through a second TOAD according to the information contained in the header. A comprehensive theoretical analysis supported by computer simulations has been carried out to study characteristics of crosstalk, noises, signal to noise ratio (SNR), Bit error rate (BER), and power penalty of the router. The results obtained, whenever possible, have been compared with the experimented data.The performance analysis of the all optical router is shown by the simulation results. The proposed router is capable of routing packet containing data in excess of 250 Gb/s all in optical domain. New models of all optical router with multi-input and outputs have been developed i.e. 1x4 router, 2x2 router, which are based on 1x2 TOAD routers. Results show that threshold switching energy is present at 0.2 pJ. Higher values result in a decrease in crosstalk and lower values result in negligible switching. Also shown is crosstalk induced penalty depends on the crosstalk level of individual 1x2 switches as well as on the size and architecture of the switching fabric.Finally, it has been shown that the proposed all-optical router has potentially useful characteristics as a component for high-speed optical TDM networks due to its ultrafast switching capability compared with existing devices. At this stage a simple 8 by 8 Banyan network is presented, however further work will enhance the model to a network with more inputs and outputs.