Spelling suggestions: "subject:"wavelengthdivision multiplexing"" "subject:"wavelengthconversion multiplexing""
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All-optical signal processing techniques to alleviate homodyne crosstalk in optical networks.January 2004 (has links)
Ku Yuen Ching. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 59-62). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Overview of optical networking --- p.1 / Chapter 1.2 --- Multi-wavelength optical networks --- p.3 / Chapter 1.2.1 --- Building blocks --- p.3 / Chapter 1.2.2 --- Performance limitations --- p.6 / Chapter 1.3 --- Related work about homodyne crosstalk --- p.8 / Chapter 1.4 --- The motivation of this thesis --- p.9 / Chapter 1.5 --- Outline of this thesis --- p.10 / Chapter 2 --- Crosstalk in WDM Networks --- p.11 / Chapter 2.1 --- Introduction --- p.11 / Chapter 2.2 --- Classification of optical crosstalk --- p.11 / Chapter 2.2.1 --- Nonlinear crosstalk --- p.12 / Chapter 2.2.2 --- Linear crosstalk --- p.13 / Chapter 2.3 --- Crosstalk characteristics --- p.14 / Chapter 2.3.1 --- Polarization states --- p.16 / Chapter 2.3.2 --- Wavelengths --- p.17 / Chapter 2.3.3 --- Phases --- p.17 / Chapter 2.4 --- Crosstalk mitigation techniques --- p.18 / Chapter 2.4.1 --- Manchester-encoding --- p.18 / Chapter 2.4.2 --- Bit-pattern misalignment --- p.19 / Chapter 2.4.3 --- Intra-bit modulation --- p.20 / Chapter 2.4.4 --- Phase scrambling --- p.20 / Chapter 2.5 --- Performance analysis --- p.21 / Chapter 2.5.1 --- Gaussian approximation --- p.22 / Chapter 2.5.2 --- Saddlepoint approximation --- p.24 / Chapter 2.5.3 --- Modified Chernoff bound --- p.25 / Chapter 2.5.4 --- Comparison --- p.26 / Chapter 2.6 --- Summary --- p.26 / Chapter 3 --- Optical Regeneration for Crosstalk Mitigation --- p.28 / Chapter 3.1 --- Introduction --- p.28 / Chapter 3.2 --- Optical regeneration techniques --- p.28 / Chapter 3.2.1 --- Fiber based gate --- p.30 / Chapter 3.2.2 --- Semiconductor based gate --- p.31 / Chapter 3.3 --- Crosstalk mitigation using SOA-MZI --- p.33 / Chapter 3.3.1 --- The experimental setup --- p.35 / Chapter 3.3.2 --- All-active SOA-MZI --- p.36 / Chapter 3.3.3 --- Results and discussion --- p.36 / Chapter 3.3.4 --- Summary --- p.39 / Chapter 3.4 --- Crosstalk mitigation using SPM spectrum filtering --- p.39 / Chapter 3.4.1 --- The experimental setup --- p.40 / Chapter 3.4.2 --- Results and discussion --- p.41 / Chapter 3.4.3 --- Summary --- p.44 / Chapter 4 --- Polarimetric Approach for Crosstalk Mitigation for Both 00K and DPSK Format --- p.45 / Chapter 4.1 --- Introduction --- p.45 / Chapter 4.2 --- Experimental setup --- p.46 / Chapter 4.3 --- Results and discussion --- p.47 / Chapter 4.4 --- Summary --- p.49 / Chapter 5 --- Crosstalk Accumulation Analysis --- p.50 / Chapter 5.1 --- Introduction --- p.50 / Chapter 5.2 --- Theory and model --- p.51 / Chapter 5.3 --- Results and discussion --- p.54 / Chapter 5.4 --- Summary --- p.56 / Chapter 6 --- Summary and Future Works --- p.57 / Chapter 6.1 --- Summary of the thesis --- p.57 / Chapter 6.2 --- Future works --- p.58 / Bibliography --- p.59 / Chapter A. --- Appendix A - List of publications --- p.63
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Monitoring of dynamic all-optical network.January 2012 (has links)
本文提出一种新颖的动态全光网络监控分布式算法,该算法可估计光网络中光纤链路上的误码率,在不需要额外光监控元件的情况下同时监控,检测和定位多处光纤链路损坏。 / 在光网络传输过程中,各个终端结点的接受机可以时时地估计出收到光流的误码率,这些误码率信息可以通过扩展OSPF-TE协议在全网共享。基于这些共享的误码率信息,我们将光纤损坏检测问题抽像成一个线性编程(LP)算法,其中每一个误码率信息代表一个限制条件。我们之后运用一些算法优化技巧将这个问题的维度和复杂度大大地降低,以便可以直接嵌入到每个网络结点可能自带的微处理器单元中进行实时计算运用。本文提出的算法同时适用于没有光波长转换器的光网络和配备光波长转换器的光网络。 通过沿用OSPF协议的分层多域思想,大规模网络可以分化成小的域和连接各域的主干网络,从而可以将一个复杂的大规模网络检错问题转化成一系列简单小网络检错问题。通过将该算法在一个由408 节点组成,支持40波长的大规模GMPLS 网络仿真平台上仿真,算法的有效性得到了验证。 / 为了保证用于仿真的网络流量模型合理且符合实际,本文也对动态全光网络流量模型做了一定研究。在自相似网络流量模型下,我们发现长短光流的不公平性问题可以给动态全光网络带来很大问题,会大大地降低网络的吞吐率。我们运用一种截短长光流的方法可以将这个问题很有效地解决。 / 据我们所知,这是目前唯一的一个能运用于现实中超大规模光网络的低成本可实现且可以作到波长级监控和同时监控多个链路错误的算法。该方法可以不用额外添加昂贵的光监控元件就可实现对动态全光网络的监控,并且该方法同时适用于透明,半透明及配置波长转换器的光网络。 / A new and efficient distributed algorithm for estimating the bit-error-rate (BER) of links in dynamic optical networks is proposed. The method can be used to monitor, detect and localize multiple soft link-failures without incurring any additional optical monitoring equipment. During the transmission of each optical flow the end node’s receiver can estimate the digital BER information, and the BER information can be shared among the network by extending the Open Shortest Path First-Traffic Engineering Extension (OSPF-TE) protocol easily. We model the faults localization problem as a linear programming (LP) algorithm, where each BER information measured from a flow serves as a constraint. Optimization techniques are applied to significantly simplify the complexity of the LP algorithm in order to make it solvable in real time by an integrated processor attached to the network node. The proposed algorithm is capable of monitoring networks with or without wavelength converters. A large scale network can be divided into several layers according to the OSPF protocol, thus the algorithm can be applied to large networks in the real world similar to OSPF. The monitoring algorithm is demonstrated by network simulations over a 408-node, 40-wavelength network test-bed where up to twenty faulty links are identified. / To make sure the traffic generator model is reasonable, the traffic model for dynamic all-optical network is also studied in this work. Under self-similar traffic, we found that the dynamic optical networks suffer from the long flow short flow unfairness problem, which would reduce the throughput as well. So a segmentation strategy is proposed to solve this problem. / To the best of our knowledge, this is the first realistic and low-cost framework which can monitor channel level BER changes to identify multi-link-failures efficiently for large scale dynamic all-optical WDM networks, without using expensive optical monitors or additional supervisory channels. The approach proposed is applicable to transparent, translucent and wavelength-converted optical networks. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Li, Huadong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 64-66). / Abstracts also in Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Backgrounds --- p.11 / Chapter 2.1 --- ROADMs, Dynamic networks --- p.11 / Chapter 2.1 --- Types of failures considered: --- p.13 / Chapter 2.2 --- Brief review of OSPF routing protocol --- p.15 / Chapter Chapter 3 --- Traffic model used --- p.16 / Chapter 3.1 --- Introduction --- p.16 / Chapter 3.2 --- LFSF unfairness problem --- p.19 / Chapter 3.3 --- Flow segmentation strategy --- p.23 / Chapter 3.4 --- Simulation results --- p.24 / Chapter 3.5 --- Summary and Conclusion --- p.29 / Chapter Chapter 4 --- Estimated digital BER monitoring and faults diagnosis algorithm --- p.31 / Chapter 4.1 --- Intra-domain faults diagnosis algorithm --- p.31 / Chapter 4.2 --- Hierarchically layering scheme for inter-domain network monitoring --- p.37 / Chapter Chapter 5 --- Simulation results and analysis --- p.40 / Chapter 5.1 --- Simulation set up --- p.40 / Chapter 5.1.1 --- 100Gbps simulation set up --- p.40 / Chapter 5.1.2 --- 10Gbps simulation set up --- p.42 / Chapter 5.2 --- Simulation results --- p.44 / Chapter 5.2.1 --- 100Gbps simulation results: --- p.44 / Chapter 5.2.2 --- 10Gbps simulation: --- p.51 / Chapter 5.3 --- Conclusion --- p.61 / Chapter Chapter 6 --- Conclusion --- p.62 / Reference --- p.64
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Multi-wavelength all-optical regeneration based on self-phase modulation and inter-channel walk-off control in fiber.January 2009 (has links)
Chong, Kin Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (p. 58-63). / Abstract also in Chinese. / Acknowledgement --- p.i / Abstract --- p.ii / 摘要 --- p.iv / Table of contents --- p.vi / List of figures and tables --- p.viii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1. --- Overview of optical regeneration --- p.1 / Chapter 1.1.1. --- O-E-O regeneration --- p.3 / Chapter 1.1.2. --- All-optical regeneration --- p.5 / Chapter 1.2. --- Motivation of this thesis --- p.7 / Chapter 1.3. --- Outline of this thesis --- p.9 / Chapter Chapter 2 --- Previous schemes of all-optical regeneration --- p.10 / Chapter 2.1. --- Introduction --- p.10 / Chapter 2.2. --- Fiber-based all-optical regeneration --- p.12 / Chapter 2.2.1. --- SPM-based regeneration --- p.12 / Chapter 2.2.2. --- FWM-based regeneration --- p.15 / Chapter 2.3. --- Semiconductor-based all-optical regeneration --- p.18 / Chapter 2.3.1. --- XGM-based regeneration --- p.18 / Chapter 2.3.2. --- XAM-based regeneration --- p.20 / Chapter 2.4. --- Multi-wavelength regeneration --- p.22 / Chapter 2.5. --- Summary --- p.23 / Chapter Chapter 3 --- Multi-wavelength optical 2R regeneration utilizing self-phase modulation and inter-channel walk-off control in fiber --- p.25 / Chapter 3.1. --- Introduction --- p.25 / Chapter 3.2. --- System architecture of the regenerator --- p.27 / Chapter 3.3. --- Experimental setup --- p.28 / Chapter 3.4. --- Results and discussions --- p.32 / Chapter 3.4.1. --- Effects of the improper inter-channel walk-off --- p.35 / Chapter 3.4.2. --- Effects of the improper filter offset --- p.36 / Chapter 3.5. --- Summary --- p.39 / Chapter Chapter 4 --- Investigation of the scalability and cascadability of our proposed multi-wavelength regeneration scheme --- p.40 / Chapter 4.1. --- Introduction --- p.40 / Chapter 4.2. --- Simulation models and results --- p.41 / Chapter 4.2.1. --- 10x10-Gb/s scenario --- p.41 / Chapter 4.2.2. --- 4x40-Gb/s scenario --- p.47 / Chapter 4.3. --- Discussions --- p.51 / Chapter 4.4. --- Summary --- p.53 / Chapter Chapter 5 --- Conclusion and future works --- p.54 / Chapter 5.1. --- Summary of the thesis --- p.54 / Chapter 5.2. --- Future works --- p.55 / List of publications --- p.57 / Bibliography --- p.58
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Regenerator placement and fault management in multi-wavelength optical networks.January 2011 (has links)
Shen, Dong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (p. 98-106). / Abstracts in English and Chinese. / Abstract --- p.i / 摘要 --- p.iv / Acknowledgements --- p.v / Table of Contents --- p.vi / Chapter Chapter 1 --- Background --- p.1 / Chapter 1.1 --- Translucent Optical Networks --- p.1 / Chapter 1.1.1 --- The Way Towards Translucent --- p.1 / Chapter 1.1.2 --- Translucent Optical Network Architecture Design and Planning --- p.3 / Chapter 1.1.3 --- Other Research Topics in Translucent Optical Networks --- p.6 / Chapter 1.2 --- Fault Monitoring in All-Optical Networks --- p.12 / Chapter 1.2.1 --- Fault Monitoring in Network Layer's Perspective --- p.12 / Chapter 1.2.2 --- Passive Optical Monitoring --- p.14 / Chapter 1.2.3 --- Proactive Optical Monitoring --- p.16 / Chapter 1.3 --- Contributions --- p.17 / Chapter 1.3.1 --- Translucent Optical Network Planning with Heterogeneous Modulation Formats --- p.17 / Chapter 1.3.2 --- Multiplexing Optimization in Translucent Optical Networks --- p.19 / Chapter 1.3.3 --- An Efficient Regenerator Placement and Wavelength Assignment Scheme in Translucent Optical Networks --- p.20 / Chapter 1.3.4 --- Adaptive Fault Monitoring in All-Optical Networks Utilizing Real-Time Data Traffic --- p.20 / Chapter 1.4 --- Organization of Thesis --- p.22 / Chapter Chapter 2 --- Regenerator Placement and Resource Allocation Optimization in Translucent Optical Networks --- p.23 / Chapter 2.1 --- Introduction --- p.23 / Chapter 2.2 --- Translucent Optical Network Planning with Heterogeneous Modulation Formats --- p.25 / Chapter 2.2.1 --- Motivation and Problem Statements --- p.25 / Chapter 2.2.2 --- A Two-Step Planning Algorithm Using Two Modulation Formats to Realize Any-to-Any Topology Connectivity --- p.28 / Chapter 2.2.3 --- Illustrative Examples --- p.30 / Chapter 2.2.3 --- ILP Formulation of Minimizing Translucent Optical Network Cost with Two Modulation Formats under Static Traffic Demands --- p.34 / Chapter 2.2.4 --- Illustrative Numeric Examples --- p.42 / Chapter 2.3 --- Resource Allocation Optimization in Translucent Optical Networks --- p.45 / Chapter 2.3.1 --- Multiplexing Optimization with Auxiliary Graph --- p.45 / Chapter 2.3.2 --- Simulation Study of Proposed Algorithm --- p.51 / Chapter 2.3.3 --- An Efficient Regenerator Placement and Wavelength Assignment Solution --- p.55 / Chapter 2.3.4 --- Simulation Study of Proposed Algorithm --- p.60 / Chapter 2.4 --- Summary --- p.64 / Chapter Chapter 3 --- Adaptive Fault Monitoring in All-Optical Networks Utilizing Real-Time Data Traffic --- p.65 / Chapter 3.1 --- Introduction --- p.65 / Chapter 3.2 --- Adaptive Fault Monitoring --- p.68 / Chapter 3.2.1 --- System Framework --- p.68 / Chapter 3.2.2 --- Phase 1: Passive Monitoring --- p.70 / Chapter 3.2.3 --- Phase 2: Proactive Probing --- p.71 / Chapter 3.2.4 --- Control Plane Design and Analysis --- p.80 / Chapter 3.2.5 --- Physical Layer Implementation and Suggestions --- p.83 / Chapter 3.3 --- Placement of Label Monitors --- p.83 / Chapter 3.3.1 --- ILP Formulation --- p.84 / Chapter 3.3.2 --- Simulation Studies --- p.86 / Chapter 3.3.3 --- Discussion of Topology Evolution Adaptiveness --- p.93 / Chapter 3.4 --- Summary --- p.95 / Chapter Chapter 4 --- Conclusions and Future Work --- p.95 / Chapter 4.1 --- Conclusions --- p.96 / Chapter 4.2 --- Future Work --- p.97 / Bibliography --- p.98 / Publications during M.Phil Study --- p.105
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Internetworking architectures for optical network units in a wavelength division multiplexed passive optical network.January 2007 (has links)
Zhao, Qiguang. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 72-76). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Telecommunications network hierarchy --- p.2 / Chapter 1.2 --- PON architectures for access networks --- p.4 / Chapter 1.2.1 --- TDM-PON --- p.5 / Chapter 1.2.2 --- WDM-PON --- p.7 / Chapter 1.3 --- Motivation of this thesis --- p.8 / Chapter 1.4 --- Outline of this thesis --- p.11 / Chapter Chapter 2 --- Previous Internetworking Architectures for Optical Network Units in Passive Optical Networks --- p.12 / Chapter 2.1 --- Introduction --- p.13 / Chapter 2.2 --- Previous internetworking architectures with ONU-broadcast capability / Chapter 2.2.1 --- Virtual ring network construction --- p.14 / Chapter 2.2.2 --- Reflection mechanism employing a FBG --- p.15 / Chapter 2.2.3 --- Loop-back mechanism in TDM-PON --- p.16 / Chapter 2.3 --- Previous internetworking architectures with ONU-VPGs formation capability --- p.17 / Chapter 2.3.1 --- E-CDMA application --- p.17 / Chapter 2.3.2 --- SCM technique --- p.18 / Chapter 2.3.3 --- Reflective waveband grouping mechanism --- p.20 / Chapter 2.4 --- Previous protection scheme for internetworking architectures --- p.21 / Chapter 2.4.1 --- Local ring protection in TDM-PON --- p.21 / Chapter 2.5 --- Summary --- p.22 / Chapter Chapter 3 --- Novel Internetworking Architecture with ONU-Broadcast Capability in a WDM-PON --- p.24 / Chapter 3.1 --- Introduction --- p.25 / Chapter 3.2 --- Network topology and wavelength assignment --- p.26 / Chapter 3.3 --- Operation principle --- p.27 / Chapter 3.4 --- Experimental demonstration --- p.31 / Chapter 3.5 --- Power budget and scalability --- p.34 / Chapter 3.6 --- Summary --- p.36 / Chapter Chapter 4 --- Novel Internetworking Architectures with ONU- VPGs Formation Capability in a WDM-PON --- p.37 / Chapter 4.1 --- Introduction --- p.38 / Chapter 4.2 --- Novel architecture with ONU-VPGs formation based on RF tone technique --- p.39 / Chapter 4.2.1 --- Introduction --- p.39 / Chapter 4.2.2 --- Network topology and wavelength assignment --- p.40 / Chapter 4.2.3 --- Media access control protocol: CSMA/CA protocol --- p.42 / Chapter 4.2.4 --- Experimental demonstration --- p.43 / Chapter 4.2.5 --- Discussion --- p.47 / Chapter 4.2.6 --- Summary --- p.49 / Chapter 4.3 --- Novel architecture with ONU-VPGs formation in optical layer --- p.51 / Chapter 4.3.1 --- Introduction --- p.51 / Chapter 4.3.2 --- Network topology and wavelength assignment --- p.51 / Chapter 4.3.3 --- Operation principle --- p.54 / Chapter 4.3.4 --- Experimental demonstration --- p.56 / Chapter 4.3.5 --- Discussion --- p.58 / Chapter 4.3.6 --- Summary --- p.65 / Chapter 4.4 --- Comparisons --- p.66 / Chapter 4.5 --- Summary --- p.67 / Chapter Chapter 5 --- Summary and Future Works --- p.68 / Chapter 5.1 --- Summary of the thesis --- p.69 / Chapter 5.2 --- Future works --- p.70 / LIST OF PUBLICATIONS --- p.71 / BIBLIOGRAPHY --- p.72
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Ultra-thin Thin-film Filters and Their Applications on WDM SystemsChou, Tzu-Hung 14 June 2005 (has links)
The subject of this dissertation is to use precision cutting and polishing techniques to fabricate thin-film filters(TFFs) with a thickness of less than 100 £gm, and to discuss their applications in Wavelength Division Multiplexing(WDM) systems. To demonstrate the feasibility of the proposed technology, Si benches with wet-etching V grooves for precision fiber positioning and saw-cutting U grooves for placing the TFFs were fabricated. The insertion loss of the bench at 1.55 £gm input lights is less than - 0.5 dB.
In addition, the stress induced pass band variations of band-pass TFF for Coarse WDM(CWDM) applications were studied. The pass band width of the band-pass TFF is 20 nm. After reducing the thickness of the 1.5 mm ¡Ñ 1.5 mm BP TFF to a thickness of 50 £gm, the center wavelength shift and pass band reduction are 4.64 nm and 1.54 nm, respectively.
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Dense wavelength division multiplexing (DWDM) for optical networksQiao, Jie. January 2001 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI Company.
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Design and analysis of survivable WDM optical networkMao, Minjing., 毛忞婧. January 2012 (has links)
Optical networks with Wavelength Division Multiplexing (WDM) technology provide huge bandwidth to meet the ever-increasing traffic demand of the next generation Internet. But the high-speed nature of WDM networks also makes the network more vulnerable to failures. Even a single network failure for a very short duration can result in enormous loss of data. In this thesis, we concentrate on designing a survivable WDM network. In essence, survivability concerns two important aspects, fast fault detection and localization, and fast fault recovery.
We first study fast fault detection and localization in WDM optical networks. Our work is based on the notion of monitoring cycle (m-cycle). Compared with other fault detection schemes, an m-cycle based fault detection scheme provides fast fault detection and requires less number of expensive monitors. Aiming at further cutting down the implementation cost, we propose the notion of super monitor. Instead of having a dedicated monitor for each m-cycle, a single super monitor can be placed at the junction of a set of overlapped m-cycles. In this thesis, we formulate and solve the monitor placement problem.
We then focus on enhancing the capacity efficiency of fast fault recovery schemes. Shared backup path protection (SBPP) schemes can provide 100% protection against any single link failure. This is achieved by establishing a pair of link-disjoint active and backup paths upon each call arrival. The bandwidth on different backup paths can be shared for protecting different calls. In this thesis, a new SBPP scheme is designed based on a two-step routing approach, where the active and backup paths are sequentially optimized with different objectives in mind. We then shift our focus to design fast protection scheme for multicast/broadcast communications. To this end, we refine the existing concept of blue/red tree. Blue/red tree is a pair of spanning trees where the connectivity between the root and any destination node is ensured upon a network failure. In particular, two efficient integer linear programs (ILPs) are formulated for finding the optimal blue/red trees.
Last but not the least, we investigate the survivability in IP networks. We notice that existing efforts on IP fast reroute (IPFRR) are effective in enhancing the IP resilience. But the impact of IPFRR on the end-to-end TCP performance is ignored. Notably, path rerouting can interfere with the TCP congestion control mechanism and thus cause severe throughput degradation. To address this problem, we propose a duplicate acknowledgement (ACK) suppression scheme. The key idea is to detect whether an out-of-order packet arrival event is due to IPFRR or not. If it is due to IPFRR, duplicate ACKs triggered will be suppressed by the TCP receiver so as not to cause unnecessary slow down at the TCP sender. / published_or_final_version / Electrical and Electronic Engineering / Doctoral / Doctor of Philosophy
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High performance dense wavelength division multiplexing/demultiplexing based on blazed grating and ion-exchanged glass waveguide techniqueZou, Jizuo 28 August 2008 (has links)
Not available / text
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Survivable routing in WDM networks with guaranteed minimum network bandwidthWang, Ye January 2007 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2007. / Includes bibliographical references. / vi, 47 leaves, bound ill. 29 cm
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