Heterogeneous Cellular Networks

Contributors xiii Preface xv 1 Overview of Heterogeneous Networks 1 1.1 Motivations for Heterogeneous Networks 2 1.1.1 Explosive Growth of Data Capacity Demands 2 1.1.2 From Spectral Efficiency to Network Efficiency 3 1.1.3 Challenges in Service Revenue and Capacity Investment 5 1.2 Definitions of Heterogeneous Networks 5 1.3 Economics of Heterogeneous Networks 6 1.3.1 Total Cost of Ownership 7 1.3.2 Heterogeneous Networks Use Scenarios 8 1.3.3 General Tends in Heterogeneous Networks Development 10 1.4 Aspects of Heterogeneous Network Technology 10 1.4.1 RF Interference 10 1.4.2 Radio System Configuration 12 1.4.3 Network Coupling 13 1.4.4 User and Device Credential 14 1.4.5 Interworking 15 1.4.6 Handover 16 1.4.7 Data Routing 18 1.4.8 Quality of Service 19 1.4.9 Security and Privacy 21 1.4.10 Capacity and Performance Evaluation 22 1.5 Future Heterogeneous Network Applications 22 References 24 Part I Radio Resource and Interference Management 2 Radio Resource and Interference Management for Heterogeneous Networks 29 2.1 Introduction 29 2.2 Heterogeneous Networks Deployment Scenarios and Interference Management Categories Based on Spectrum Usage 31 2.2.1 Heterogeneous Network Deployment Scenarios 31 2.2.2 Interference Management Categories Based on Spectrum Usage 33 2.3 Multi-carrier Inter-cell Interference Management for Heterogeneous Networks 33 2.3.1 Interference Management via Carrier Partitioning 34 2.3.2 Enhanced Carrier Reuse with Power Control 36 2.3.3 Carrier Aggregation Based Inter-cell Interference Coordination 36 2.4 Co-channel Inter-cell Interference Management for Heterogeneous Networks 38 2.4.1 Control Channel Interference Management 39 2.4.2 Data Channel Interference Management 46 2.5 Conclusion 48 References 48 3 Capacity and Coverage Enhancement in Heterogeneous Networks 51 3.1 Introduction 52 3.2 Deployment Scenarios 54 3.2.1 Multi-tier Network Elements 54 3.2.2 Multi-radio Techniques 55 3.3 Multi-tier Interference Mitigation 56 3.3.1 Multi-tier Spectral Reuse Scenarios 56 3.3.2 Cross-tier Interference 56 3.3.3 Network Synchronization for IM 57 3.3.4 Overview of Interference Mitigation Techniques 57 3.3.5 Performance Comparison of IM Schemes 60 3.4 Multi-radio Performance 61 3.5 Standardization and Future Research Directions 62 3.5.1 Status of Wireless Standards 62 3.5.2 Future Research Directions 62 3.6 Conclusion 64 References 64 4 Cross-tier Interference Management in 3GPP LTE-Advanced Heterogeneous Networks 67 4.1 Introduction 67 4.1.1 Heterogeneous Network Deployments 68 4.1.2 OSG Scenario 68 4.1.3 CSG Scenario 70 4.2 Interference Management for LTE and LTE-Advanced Networks 70 4.2.1 Interference Management Methods for Homogenous Networks 71 4.2.2 Interference Management for Heterogeneous Networks 73 4.2.3 Time Domain Based ICIC Schemes 74 4.2.4 Power Setting for Femtocells 85 4.3 Conclusions 89 Appendix: Simulation Models 89 References 92 5 Inter-cell Interference Management for Heterogeneous Networks 93 5.1 Introduction 93 5.2 Conventional Inter-cell Interference Coordination 95 5.3 Enhanced Inter-cell Interference Coordination 98 5.3.1 Interference Scenarios in Heterogeneous Networks 98 5.3.2 Enhanced ICIC Solutions for Heterogeneous Networks 100 5.4 Conclusion 116 References 116 6 Cognitive Radios to Mitigate Interference in Macro/femto Heterogeneous Networks 119 6.1 Introduction 119 6.2 Information Requirement and Acquisition for Interference Mitigation 122 6.3 Descriptions of System Models 124 6.3.1 Two-tier Network Architecture 124 6.3.2 Channel Model 124 6.3.3 Traffic Model 125 6.3.4 CR-enabled Operations 125 6.4 Cross-tier Interference Mitigation 125 6.4.1 Interference Coordination: Orthogonality in the Time/Frequency Domain 125 6.4.2 Interference Coordination: Orthogonality in the Antenna Spatiality Domain 126 6.4.3 Interference Cancellation: Coding Techniques 129 6.5 Intra-tier Interference Mitigation 130 6.5.1 Strategic Game for Collocated Femtocells 131 6.5.2 Gibbs Sampler for Collocated Femtocells 132 6.6 Interference Mitigation for Machine-to-Machine Communications 136 6.6.1 Background of Compressive Sensing 138 6.6.2 SMRM for Femtocells 138 6.6.3 Compressive Sensing for the Spectrum Map Construction 140 6.6.4 Performance Evaluations 140 6.7 Conclusion 141 References 142 7 Game Theoretic Approach to Distributed Bandwidth Allocation in OFDMA-based Self-organizing Femtocell Networks 145 7.1 Introduction 145 7.2 Distributed Bandwidth Allocation 146 7.3 Convergence Analysis 150 7.4 Choice of Utility Function and its Parameters 152 7.5 Simulation Results 155 7.5.1 Convergence Studies 156 7.5.2 Bandwidth Allocation and Network Tuning 156 7.6 Extensions and Discussions 159 7.7 Conclusion 162 Acknowledgement 162 References 162 Part II Mobility and Handover Management 8 Mobility Management and Performance Optimization in Next Generation Heterogeneous Mobile Networks 167 8.1 Introduction 167 8.2 Overview of Mobility Management in RRC-connected State 168 8.3 Mobility Robustness Optimization 171 8.4 Mobility Load Balancing Optimization 176 8.4.1 Related Works 177 8.4.2 Problem Description 177 8.4.3 Load Balancing Algorithm with Penalized Handovers 180 8.4.4 Numerical Examples 182 8.5 Cooperation of MRO and MLB 185 8.5.1 Achieve Load Balance by Adjusting CI O 186 8.5.2 Coordination Rules between MRO and MLB 186 8.5.3 Jointly Consider MRO and MLB 187 8.5.4 Simulation Results 188 8.6 Mobility Enhancement for Femtocells 192 8.7 Conclusion 194 Acknowledgements 195 References 195 9 Connected-mode Mobility in LTE Heterogeneous Networks 199 9.1 Introduction 199 9.2 Cell Selection and Problem Statement 200 9.3 Simulation Methodology 202 9.4 Handover Modelling 207 9.5 Results 210 Reference 214 10 Cell Selection Modes in LTE Macro-Femtocell Deployment 215 10.1 Introduction 215 10.2 Distinction of Cells 216 10.3 Access Control 219 10.3.1 Access Control Scenarios 220 10.3.2 Access Control Executor 220 10.3.3 Access Control Mechanisms 223 10.3.4 Performance of Access Control Mechanisms 225 10.4 Cell Selection and Cell Reselection 231 10.4.1 UE in Idle Mode 232 10.4.2 PLMN Selection 234 10.4.3 Cell Selection 235 10.4.4 Cell Reselection 239 10.4.5 Cell Reselection with Femtocells 241 References 244 11 Distributed Location Management for Generalized HetNets. Case Study of All-wireless Networks of Femtocells 247 11.1 Introduction 247 11.1.1 Motivation 248 11.1.2 Approach 249 11.1.3 On Location Management in Generalized HetNets 250 11.2 Background on Geographic Routing and Geographic Location Management 250 11.3 All-wireless Networks of Femtocells 252 11.3.1 Challenges of All-wireless Networks of Femtocells 253 11.4 Architecture for Geographic-based All-wireless Networks of Femtocells 254 11.4.1 Overview of the Architecture 254 11.4.2 Network Entities Supporting Networks of Femtocells 255 11.4.3 Operation of the Network of Femtocells 256 11.4.4 Sample Protocol Stacks for Wifi-based All-wireless NoFs 257 11.4.5 Other Relevant Issues 257 11.5 Location Management Procedures 258 11.5.1 Paging 259 11.5.2 Handoff 260 11.6 Summary and Conclusions 262 Acknowledgements 263 References 263 12 Vertical Handover in Heterogeneous Networks: a Comparative Experimental and Simulation-based Investigation 265 12.1 Introduction 265 12.2 Preliminaries on VHO 266 12.3 Experimental Investigation 267 12.3.1 VHO Decision Algorithms 267 12.3.2 Experimental Setup and Results 270 12.4 Simulation-based Investigation 274 12.4.1 The OPNET Simulator 274 12.4.2 Performance Results 276 12.5 Discussion on the VHO in HetNets 283 12.5.1 Role of the (Internal) Decision Algorithm 283 12.5.2 Role of the Authentication Procedures 283 12.5.3 Impact of VHO on HetNet Coverage 284 12.5.4 Impact of VHO on HetNet Capacity 284 12.6 Conclusions 284 Acknowledgment 285 References 285 Part III Deployment, Standardization and Field Trials 13 Evolution of HetNet Technologies in LTE-advanced Standards 289 13.1 Introduction 289 13.2 Deployment Scenarios for LTE-advanced HetNet 290 13.2.1 Macro-Femto Scenario 291 13.2.2 Macro-Pico Scenario 292 13.3 Inter-cell Interference Coordination for HetNet 292 13.3.1 Rel-8/9 ICIC 293 13.3.2 Rel-10 Enhanced ICIC 294 13.3.3 System-level Performance of HetNet with Time-domain eICIC 299 13.4 Ongoing Work in Rel-11 LTE-A 305 13.4.1 Support of Non-zero Power ABS 306 13.4.2 Network-assisted Cell Acquisition for CRE UE in Low Geometry 308 13.4.3 Mitigation of CRS Interference for CRE UE in Low Geometry 309 13.5 Conclusion 310 References 310 14 Macro-Femto Heterogeneous Network Deployment and Management 313 14.1 Introduction 314 14.2 Frameworks for Macro-Femto Network Deployment and Management 315 14.2.1 Joint-deployment Framework 315 14.2.2 WSP-deployment Framework 318 14.2.3 User-deployment Framework 318 14.3 Revenue Maximization with WSP-deployed Femto-BSs 319 14.3.1 On Cross-tier Channel Allocation 320 14.3.2 On Optimal Pricing and Spectrum Partition 326 14.4 Summary 332 References 333 15 Field Trial of LTE Technology 335 15.1 Introduction 335 15.2 Field Trial Overview 336 15.2.1 UE Antennas 337 15.2.2 Network Configuration and Field Trial Setup 338 15.3 Measurement Results 338 15.4 Summary Comparison 344 15.5 Conclusion 346 References 347 Index 349