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Quality of Service Oriented Traffic Engineering

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Quality of Service oriented Traffic Engineering Methods for Multi-Service Cellular Networks Dienstgüte-orientierte verkehrstheoretische Methoden für die Bereitstellung unterschiedlicher Dienste in zellularen Netzen Der Technischen Fakultät der Universität Erlangen-Nürnberg zur Erlangung des Grades DOKTOR INGENIEUR vorgelegt von LARISSA N. POPOVA Erlangen – 2009 Als Dissertation genehmigt von der Technischen Fakultät der Friedrich-Alexander-Universität Erlangen-Nürnberg Tag der Einreichung: 07. Dezember 2009 Tag der Promotion: 12. February 2010 Dekan: Prof. Dr.-Ing. Reinhard German Berichterstatter: Prof. Dr.-Ing. Villy Baek Iversen Prof. Dr.-Ing. Wolfgang Koch To my husband Denis and my sons Konstantin and Maxim Acknowledgment First of all, I would like to thank my supervisor Prof. Wolfgang Koch, for giving me the opportunity to pursue my Ph.D. at his Institute of Mobile Communication and for providing an environment where it was a pleasure to work. I am grateful to him for the fruitful discussions on my work, for his continued support and faith in the success of my research. I am indebted to Prof. Villy Baek Iversen for his kind-hearted mentoring, for reviewing my thesis, and for making my memorable stay at Technical University of Denmark, Lyngby, possible. I am very grateful to Dr. Wolfgang Gerstacker for his interest in my work, for his great encouragement, and for finding time to participate in the defense of this work. I would also like to thank all my colleagues at the Telecommunications Laboratory in Erlangen for creating pleasant and humorous atmosphere. Special thanks go to my roommate Armin Schmidt, for interesting scientific and non- scientific discussions, as well as for his technical LaTeX support. Finally, I would like to give thanks to my parents, Liudmila and Nikolay for their con- tinued love and support. And my deepest thanks I owe to my husband, Denis, who tireless supported me to the realization of my thesis, for his patience and love. Contents Introduction 1 Contribution of the Thesis 3 Einführung 5 Zusammenfassung 7 1. Universal Mobile Telecommunications System (UMTS) 9 1.1. SystemArchitecture ................................ 9 1.2. WCDMAConcept ................................... 10 1.3. RadioResourceManagement............................ 12 1.4. Techniques for Radio Resource Utilization . 13 1.4.1. PowerControl ................................ 13 1.4.2. Handover Control . 14 1.4.3. Call Admission Control . 14 1.4.4. Congestion Control . 14 1.5. Summary . 15 Part I. Traffic Modeling for Wireless Networks 17 2. Traffic Concepts and Models 19 2.1. MathematicalBackground: BasicModel . 19 2.1.1. Birth-DeathProcess ............................. 19 2.2. Markovian Queuing Systems . 21 2.2.1. M/M/1System................................ 22 2.2.2. Erlang’s Loss System . 24 2.2.2.1. Blocked-Call-Cleared – Erlang B . 25 2.3. Traffic Models for Wireless Networks . 26 2.3.1. General Remarks on Existing Traffic Models: Drawbacks and Chal- lenges ..................................... 26 2.4. Summary . 29 3. Connection Level Performance Modelling for Multi-Rate Loss System with WCDMA Radio Interface 31 3.1. Motivation ....................................... 31 3.2. SingleCellCapacityModel ........................... 32 3.3. Connection dependent Model with Transmission Rate Reduction Policy . 33 3.4. Multi-CellCapacityModel. 37 viii Contents 3.4.1. Restricted Network Accessibility - Modeling of Other-Cell Inter- ference..................................... 38 3.4.2. Proposed algorithm . 39 3.5. AnalyticalSystemPerformance. 43 3.5.1. Performance evaluation analysis . 43 3.6. Summary . 45 4. Joint Connection and Packet Level Analysis for Multi-Rate Loss System with WCDMA Radio Interface 47 4.1. MotivationandRelatedWork. 47 4.2. Multi-CellTwo-LevelCapacityModel . 48 4.2.1. Connection Level . 49 4.2.2. A Novel Model for Packet Level Performance Evaluation . 49 4.2.2.1. Blocked-Call-Held (BCH) Model (Fry-Molina Model) at packetlevel ............................ 50 4.2.2.2. Blocked-Call-Interfered (BCI) . 52 4.2.3. Performance Measures . 54 4.3. PerformanceResults ................................ 56 4.3.1. Impact of the Traffic Mix . 56 4.3.2. Analyzing trends by load change . 58 4.3.3. Adjustment of loss rates at packet level . 59 4.3.4. Impact of the Activity Factor . 60 4.4. Summary . 61 5. Extended Analysis of Two-Level Performance Model for Multi-Rate Delay System with WCDMA Radio Interface 63 5.1. MotivationandRelatedWork. 63 5.1.1. On the Generality of the Algorithm . 63 5.2. Unified Analytical Traffic Model . 64 5.3. SystemPerformanceAnalysis. 66 5.3.1. CallAdmissionandHandlingPolicy . 66 5.3.2. Comparison of Blocked-Call-Buffered (BCB) model with Blocked- Call-Held(BCH) ............................... 67 5.3.3. Behavior of the System with Soft Blocking . 67 5.3.4. Probability of Getting Service without Priority Classes . 68 5.4. Summary . 70 Part II. Traffic Management for Wireless Networks 73 6. Mobile-to-Mobile: A Novel Concept for Spectrum Efficient Data Transfer in WCDMA 75 6.1. Motivation ....................................... 75 6.2. Cooperative Communications in Wireless Networks (General Concepts, Strategies,Principles) ............................... 77 6.3. Mobile-to-Mobile(M2M)Concept . 80 6.4. ConceptAnalysisandEvaluation. 83 6.4.1. Model Characteristics and Assumptions . 83 Contents ix 6.4.2. RadioInterfaceRestrictions . 83 6.4.3. M2M Propagation Model . 84 6.4.3.1. Pathloss and Shadowing . 84 6.4.3.2. Fading . 86 6.5. M2M-GroupOrganizationPolicy. 86 6.6. CooperativeDataTransferPolicy. 90 6.7. Performance Evaluation of M2M Data Transfer: Verification of Basic Func- tionality......................................... 94 6.7.1. Simulation Scenarios . 94 6.7.2. Traffic Model: Pure M2M File Transfer . 94 6.7.3. Performance Measures . 95 6.7.4. Comparison of M2M File with conventional UMTS Data Transmis- sion....................................... 95 6.7.5. ImpactofMulticastTechnique. 99 6.7.6. Impact of Group Update Interval . 100 6.7.7. Effect of the Restrictions in the Group Organization Policy . 101 6.8. Direct Mobile-to-Mobile Data Transfer for mixed traffic scenario with ser- vicedifferentiation ................................. 103 6.8.1. Traffic Model: Incorporating Speech User Population into the Model103 6.8.2. Simulation Scenarios . 103 6.8.3. Impact of Cross-Traffic on the M2M Performance: Uplink Interfer- ence.......................................104 6.8.4. Comparison of M2M File Dissemination and Conventional UMTS Data Transmission for Mixed Traffic Scenarios . 106 6.9. Dependability of Mobile-to-Mobile Data Transfer . 109 6.9.1. Practicallyrelevantschedulingpolicy . 109 6.9.2. Impact of Group Size on Inter-Group Interference . 110 6.9.3. Effect of Restricted base station (BS) Support . 112 6.10.Summary . 117 7. Enhanced Scheduling by Network Coding Supported M2M Data Transfer119 7.1. MotivationandRelatedWork. 119 7.2. NetworkCodingBasics.............................. 121 7.3. network coding (NC) applied to M2M Data Transfer . 123 7.4. NumericalResults.................................. 127 7.4.1. Simulation Environment . 127 7.4.2. Traffic Scenario . 128 7.4.3. Performance Measures . 129 7.4.4. Performance Comparison of Simple M2M Algorithm with network coding – mobile-to-mobile (NC-M2M) File Dissemination . 129 7.4.5. Impact of Extended M2M User Availability and Users’ Mobility . 130 7.4.6. Steady State System Performance . 132 7.4.7. Further Benefits of NC-M2M File Dissemination: Released Uplink . 132 7.5. Enhanced Network Coding for Operation on Data of Arbitrary Size . 134 7.5.1. Generations: Optimized Packet Combination . 134 7.6. NumericalResults.................................. 135 x Contents 7.6.1. Memory Requirements and Computational Complexity . 136 7.6.2. Analysis of Relationship between Different Figures of Merit . 137 7.6.2.1. Generation Distribution Strategy . 137 7.6.2.2. Generation Size and File Size . 138 7.6.2.3. Quality of Service (QoS) Requirements . 140 7.7. Efficient Large File Distribution in UMTS supported by Network Coded M2M Data Transfer with Multiple Generations . 142 7.7.1. Comparison of NC-MG-m2m File Sharing with Replicate-and-Forward M2M Data Dissemination . 142 7.7.1.1. Practical Issues . 144 7.8. Summary . 144 8. Conclusions 147 A. Kendall Notation 149 B. Binomial-Poisson-Pascal traffic (BPP) Paradigm 151 C. Convolution Algorithm 155 D. Advanced Propagation Models 157 List of Acronyms 161 List of Symbols 163 PartI.............................................. 163 PartII............................................. 164 List of Figures 165 List of Tables 169 Bibliography 171 Introduction The rapid growth of wireless multimedia services and their demand for high data rates put considerable load on the valuable and limited resources of cellular wireless net- works. The third generation of wireless networks makes use of the packet-switching technology to achieve higher efficiency and better utilization of the scarce radio re- sources. However, new opportunities entail new challenges. As the capabilities and flexibility of networks increase, the demand for radio resources becomes less homo- geneous. In order to provide services in a heterogeneous environment of 3G systems more efficiently, it is necessary to predict the limits of the traffic load such that upper bounds for probabilities of call blocking and packet dropping for all classes of demands can be maintained. Typically, the downlink is the potential bottleneck, since all data transmissions have to be organized by providing individual
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