Heterogeneous Cellular Networks

A timely publication providing coverage of radio resource management, mobility management and standardization in heterogeneous cellular networks

The topic of heterogeneous cellular networks has gained momentum in industry and the research community, attracting the attention of standardization bodies such as 3GPP LTE and IEEE 802.16j, whose objectives are looking into increasing the capacity and coverage of the cellular networks. This book focuses on recent progresses,  covering the related topics including scenarios of heterogeneous network deployment, interference management in the heterogeneous network deployment, carrier aggregation in a heterogeneous network, cognitive radio, cell selection/reselection and load balancing, mobility and handover management, capacity and coverage optimization for heterogeneous networks, traffic management and congestion control.

This book enables readers to better understand the technical details and performance gains that     are made possible by this state-of-the-art technology. It contains the information necessary for researchers and engineers wishing to build and deploy highly efficient wireless networks themselves. To enhance this practical understanding, the book is structured to systematically lead the reader through a series of case-studies of real world scenarios.

Key features:

• Presents this new paradigm in cellular network domain: a heterogeneous network containing network nodes with different characteristics such as transmission power and RF coverage area
• Provides a clear approach by containing tables, illustrations, industry case studies, tutorials and examples to cover the related topics
• Includes new research results and state-of-the-art technological developments and implementation issues

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

Rose Qingyang Hu is Associate Professor in the Department of Electrical and Computer Engineering at Utah State University. Her current research interests include interference management, cooperative communications, cognitive radio, mobility, security, QoS and green networking in wireless networks.