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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Online scheduling of periodic lightpath request with flexibility

Ye, Luning January 2007 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2007. / Includes bibliographical references (leaves 44-45). / viii, 45 leaves, bound ill. 29 cm
32

Design of survivable WDM network based on pre-configured protection cycle

Kang, Byungkyu. January 2006 (has links)
Thesis (M.EngSc. )--Edith Cowan University, 2006. / Submitted to the Faculty of Computing, Health and Science. Includes bibliographical references.
33

Design survivable WDM mesh network using path protection /

Han, Zhenjiang, January 1900 (has links)
Thesis (M.Sc.) - Carleton University, 2003. / Includes bibliographical references (p. 59-62). Also available in electronic format on the Internet.
34

SWAP a slotted wavelength assignment pipeline scheduler for next-generation optical burst switches (OBS) /

Anan, Muhammad Taqiuddin. Chaudhry, Ghulam M. January 2008 (has links)
Thesis (Ph. D.)--School of Computing and Engineering. University of Missouri--Kansas City, 2008. / "A dissertation in electrical & computer engineering and telecommunications networking." Advisor: Ghulam M. Chaudhry. Typescript. Vita. Title from "catalog record" of the print edition Description based on contents viewed Sept. 12, 2008. Includes bibliographical references (leaves 152-169). Online version of the print edition.
35

Design of optical networks: performance bounds, complexity and algorithms /

Saad, Mohamed Elsayed Mostafa. Luo, Zhi-Quan. January 2004 (has links)
Thesis (Ph.D.)--McMaster University, 2005. / Advisor: Zhi-Quan Luo. Includes bibliographical references (leaves 136-145). Also available online.
36

High performance dense wavelength division multiplexing/demultiplexing based on blazed grating and ion-exchanged glass waveguide technique

Zou, Jizuo, Chen, Ray T. January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisor: Ray T. Chen. Vita. Includes bibliographical references.
37

On coding for orthogonal frequency division multiplexing systems : a thesis presented for the degree of Doctor of Philosophy, University of Canterbury, Christchurch, New Zealand /

Clark, Alan, January 1900 (has links)
Thesis (Ph. D.)--University of Canterbury, 2006. / Typescript (photocopy). "January 2006." Includes bibliographical references (p. 139-151). Also available via the World Wide Web.
38

Fault-tolerance using shared path protection in wavelength division multiplexing optical transport networks

Todimala, Ajay Kumar. January 1900 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2006. / Title from title screen (site viewed May 23, 2007). PDF text: viii, 166 p. : ill. ; 0.85Mb UMI publication number: AAT 3236908. Includes bibliographical references. Also available in microfilm and microfiche formats.
39

Numerical modelling of optical micro-cavity ring resonators for WDM networks

Abujnah, Nabeil Abduljallil Abubaker January 2011 (has links)
Augmenting the level of integration for a lower cost and enhancing the performance of the optical devices have turned out to be the focus of many research studies in the last few decades. Many distinct approaches have been proposed in a significant number of researches in order to meet these demands. Optical planar waveguides stand as one of vital employed approach in many studies. Although, their low propagation loss, and low dispersion, they suffers from high power losses at sharp bends. For this reason, large radius of curvature is required in order to achieve high efficiency and compromise the high level of integration. For the purpose of this research, in this thesis different ways to improve the performance of optical microcavity ring resonators (MRRs) have been thoroughly investigated and new configurations have been proposed. The Multiresolution Time Domain (MRTD) technique was further developed and employed throughout this thesis as the main numerical modelling technique. The MRTD algorithm is used as a computer code. This code is developed and enhanced using self built Compaq Visual Fortran code. Creating the structure and Post-processing the obtained data is carried out using self built MATLAB code. The truncating layers used to surround the computational domain were Uniaxial Perfectly Matched Layers (UPML). The accuracy of this approach is demonstrated via the excellent agreement between the results obtained in literature using FDTD method and the results of MRTD. This thesis has focused on showing numerical efficiency of MRTD where the mesh size allowed or the total number of computed points is about half that used with FDTD. Furthermore, the MRR geometry parameters such as coupling gap size, microring radius of curvature, and waveguide width have been thoroughly studied in order to predict and optimise the device performance. This thesis also presents the model analysis results of a parallel-cascaded double-microcavity ring resonator (PDMRR). The analysis is mainly focus on the extraction of the resonant modes where the effect of different parameters of the structure on transmitted and coupled power is investigated. Also, accurate analysis of 2D coupled microcavity ring resonator based on slotted waveguides (SMRR) has been thoroughly carried out for the purpose of designing optical waveguide delay lines based on slotted ring resonator (SCROW). The SCROW presented in this thesis are newly designed to function according to the variation of the resonance coupling efficiency of a slotted ring resonators embedded between two parallel waveguides. The slot of the structures is filled with SiO2 and Air that cause the coupling efficiency to vary which in turn control both the group velocity and delay time of SCROW structures results from the changing the properties of the bent slotted waveguide modes which strongly depends on the slot’s position. Significant improvements on the quality factor and greater delay time have been achieved by introducing sub-wavelength-low-index slot into conventional waveguide.
40

Dispersion compensation in wavelength-division multiplexed optical fibre links

Saleh, Kawaya Shako 26 February 2009 (has links)
M.Ing. / Lightwave systems used in the core transport network of telecommunication systems operate in the second transmission window. The 1550 nm wavelength region exhibits the lowest attenuation coefficient, thus expanding the repeater distance in the network. However, the influence of the large dispersion coefficient associated with the second transmission window limits the operating speed of the network to 2.5 Gbit/s or less. In order for the network to operate at higher bit-rate, a dispersion management scheme is needed. In this research, the performance of negative dispersion fibre used as a dispersion compensating module is investigated. The negative dispersion fibre used in this study was the AVANEX PureForm DCM. The dispersion coefficient of the DCM measured at 1525 nm, 1545 nm and 1565 nm were given as -918 , -987 and -1047 respectively. The optimal operating condition of the DCM was obtained by considering various dispersion management configurations i.e. post-compensation, pre-compensation and symmetric compensation. The DCM was tested on a single span, single channel system operating at a speed of 10 Gbit/s with the transmitting wavelength of 1551.2 nm, over 60 km of convention single mode fibre. Furthermore, the performance of the system at 55 km and 65 km were also used to examine the results for the over- and under compensation links respectively. The results obtained for 100% dispersion cancellation for the pre-, post- and symmetric configuration showed an increase in the extinction ratio of 2.09 dB, 2.72 dB and 2.37 dB respectively. Similarly, the Q-factor was estimated to equal 13.67, 11.296 and 13.167 respectively. The results indicate similar performance for all the configurations considered, analysis of the eye-diagrams reveals that the post-compensation configuration would ultimately yield the best results. This is due to the fact that eye diagram recovered from this setup has minimal deformation. The experiments for an extremely over-compensated link, i.e. 40 km, showed an increase from 9.49, obtained with no compensation, to 10.63. However, for the extremely under-compensated link i.e. 80 km, the extinction ratio only manages to improve from 4.88 dB to 8.63 dB.

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