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Optimising the efficiency of coherent optical packet switched networks

Walsh, Anthony John (2015) Optimising the efficiency of coherent optical packet switched networks. PhD thesis, Dublin City University.

Abstract
There is a continuing need to increase throughput in optical networks to satisfy the demands of internet applications. However, the non-linear Shannon capacity of standard single mode fibre is being approached. Also, almost all of the power used in optical networks is used by electronic routers. One possible solution to deal with both problems is to use optical packet switching. Optical packet switching uses fast switching tuneable lasers, which can change wavelength in the order of a several nanoseconds, to dynamically vary wavelength assignments in a network, and thus achieve routing in the network without electronic routers. In addition, fast wavelength assignment reduces waiting times, resulting in better utilization of network resources. However, the frequency dynamics of the tuneable lasers after switching wavelengths increases the waiting times required to successfully transmit data packets. In this thesis, frequency and phase dynamics of a tuneable laser transmitter, after a wavelength switching event, are initially characterised accurately using a novel technique. The effects that the frequency dynamics have on the transmission of coherent optical communication signals are mitigated using doubly differential decoding, a new approach proposed in this work for application in optical packet switched networks. This technique reduces the waiting times required to successfully transmit data after a wavelength switching event, and this enhances overall network efficiency and throughput. In addition, this work proposes and demonstrates the use of a least-mean squares algorithm to overcome polarisation demultiplexing issues which are present in these networks, which also decreases waiting times, increases network efficiency, and improves system robustness.
Metadata
Item Type:Thesis (PhD)
Date of Award:November 2015
Refereed:No
Supervisor(s):Barry, Liam P.
Subjects:Engineering > Optical communication
Physical Sciences > Optoelectronics
Engineering > Telecommunication
Engineering > Electronic engineering
Physical Sciences > Lasers
Physical Sciences > Photonics
DCU Faculties and Centres:DCU Faculties and Schools > Faculty of Engineering and Computing > School of Electronic Engineering
Research Initiatives and Centres > Research Institute for Networks and Communications Engineering (RINCE)
Use License:This item is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 3.0 License. View License
Funders:Science Foundation Ireland
ID Code:20646
Deposited On:25 Nov 2015 14:47 by Liam Barry . Last Modified 19 Jul 2018 15:06
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