Design Of The Node Architecture For Light-Trail Network And Its Crosstalk Analysis

Light-trail (LT) network is a new type of optical switching network, which was proposed by A. Gumaste and I. Chlamtac in2003. It insists that information of several nodes can be transmitted in sequence by one optical channel by adopting the existing mature devices in the time division multiplexing (TDM) manner. In addition, the intermediate points in the LT path do not need to undertake packet burst switching or group level switching configuration in the process of information transmission. LT network has attracted more and more attention of researches owing to its low dynamic switching rate, high wavelength efficiency and the transparent bit rate, etc.On the basis of extensively review of the structures of LT network nodes and their performance, the LT network nodes architecture and its performance analysis is chosen as the research subject. A novel LT node which can support several input ports and output ports of fibers is proposed. Furthermore, a detailed verification and crosstalk analysis of the existing LT network nodes based on WDM is made by adopting the way of theoretical analysis and software simulation, which includes typical LT nodes, ring topology LT nodes and mesh topology LT nodes. Work of the thesis is summarized as follows: Firstly, due to the drawbacks that typical LT node can’t support MIMO and the directly switching operation among the input ports and output ports, a LT node which can support MIMO is devised. The node can also support both the local wavelength switching and the global wavelength switching. At the same time, it possesses the advantages of low cost and can be implemented easily.Secondly, a basic study on the crosstalk of LT network nodes is made and the budget theory of the power penalty in the optical fiber communication system is adopted. On the basis of theories above, the node model of output power for one certain port is established. And a series of formula derivation for interband crosstalk and intraband crosstalk in the communication process is done. Besides, the evaluation methods for the LT nodes’performance are also given.Finally, the simulation platform of LT optical communication system is established by adopting the Optisystem. Extensively simulations on the typical LT nodes and the ring topology LT node are made at the scenarios of CWDM and DWDM. So is the new type of LT node which is proposed in the theisi. The paper verifies the mechanism of the crosstalk and the different influence of interband crosstalk and intraband crosstalk in the LT network nodes by analyzing the simulation data. What’s more, corresponding methods for restraining the crosstalk are also proposed.