This book explains how the performance of modern cellular wireless networks can be evaluated by measurements and simulations With the roll-out of LTE, high data throughput is promised to be available to cellular users. In case you have ever wondered how high this throughput really is, this book is the right read for you: At first, it presents results from experimental research and simulations of the physical layer of HSDPA, WiMAX, and LTE. Next, it explains in detail how measurements on such systems need to be performed in order to achieve reproducible and repeatable results. The book further addresses how wireless links can be evaluated by means of standard-compliant link-level simulation. The major challenge in this context is their complexity when investigating complete wireless cellular networks. Consequently, it is shown how system-level simulators with a higher abstraction level can be designed such that their results still match link-level simulations. Exemplarily, the book finally presents optimizations of wireless systems over several cells. This book: * Explains how the performance of modern cellular wireless networks can be evaluated by measurements and simulations * Discusses the concept of testbeds, highlighting the challenges and expectations when building them * Explains measurement techniques, including the evaluation of the measurement quality by statistical inference techniques * Presents throughput results for HSDPA, WiMAX, and LTE * Demonstrates simulators at both, link- level and system-level * Provides system-level and link-level simulators (for WiMAX and LTE) on an accompanying website (href="https://www.nt.tuwien.ac.at/downloads/featured-downloads">https://www.nt.tuwien.ac.at/downloads/featured-downloads) This book is an insightful guide for researchers and engineers working in the field of mobile radio communication as well as network planning. Advanced students studying related courses will also find the book interesting.
Autorentext
Dr. Sebastian Caban, University of Technology Vienna, Austria
Sebastian Caban finished his PhD with summa cum laude in October 2009 and is now post doctoral fellow at this institute.
Christian Mehlführer, University of Technology Vienna, Austria
Christian Mehlführer received his Dipl.-Ing. degree in electrical engineering from the Vienna University of Technology. In 2009, he finished his PhD about measurement-based performance evaluation of WiMAX and HSDPA with summa cum laude.
Professor Markus Rupp, University of Technology Vienna, Austria
Markus Rupp received his Dipl.-Ing. degree in 1988 at the University of Saarbrücken, Germany and his Dr.-Ing. degree in 1993 at the Technische Universität Darmstadt, Germany, where he worked with Eberhardt Hänsler on designing new algorithms for acoustical and electrical echo compensation.
Martin Wrulich, University of Technology Vienna, Austria
Martin Wrulich received his Dipl.-Ing. degree from Vienna University of Technology in March 2006 (diploma thesis: "Capacity Analysis of MIMO systems").
Inhalt
About the Authors xiii
About the Contributors xv
Preface xvii
Acknowledgments xxiii
List of Abbreviations xxv
Part I CELLULAR WIRELESS STANDARDS
Introduction 3
References 4
1 UMTS High-Speed Downlink Packet Access 5
1.1 Standardization and Current Deployment of HSDPA 5
1.2 HSDPA Principles 6
1.2.1 Network Architecture 7
1.2.2 Physical Layer 9
1.2.3 MAC Layer 13
1.2.4 Radio Resource Management 14
1.2.5 Quality of Service Management 16
1.3 MIMO Enhancements of HSDPA 17
1.3.1 Physical Layer Changes for MIMO 19
1.3.2 Precoding 21
1.3.3 MAC Layer Changes for MIMO 25
1.3.4 Simplifications of the Core Network 26
References 26
2 UMTS Long-Term Evolution 29
Contributed by Josep Colom Ikuno
2.1 LTE Overview 29
2.1.1 Requirements 29
2.2 Network Architecture 31
2.3 LTE Physical Layer 33
2.3.1 LTE Frame Structure 34
2.3.2 Reference and Synchronization Symbols 36
2.3.3 MIMO Transmission 37
2.3.4 Modulation and Layer Mapping 39
2.3.5 Channel Coding 41
2.3.6 Channel Adaptive Feedback 45
2.4 MAC Layer 46
2.4.1 Hybrid Automatic Repeat Request 46
2.4.2 Scheduling 47
2.5 Physical, Transport, and Logical Channels 48
References 51
Part II TESTBEDS FOR MEASUREMENTS
Introduction 57
Reference 58
3 On Building Testbeds 59
3.1 Basic Idea 60
3.2 Transmitter 61
3.3 Receiver 63
3.4 Synchronization 65
3.5 Possible Pitfalls 67
3.5.1 Digital Baseband Hardware 67
3.5.2 Tool and Component Selection 68
3.5.3 Analog RF Front Ends 69
3.5.4 Cost 70
3.5.5 Matlab® Code and Testbeds 70
3.6 Summary 71
References 72
4 Quasi-Real-Time Testbedding 75
4.1 Basic Idea 75
4.2 Problem Formulation 77
4.3 Employing the Basic Idea 78
4.4 Data Collection 80
4.4.1 More Sophisticated Sampling Techniques 81
4.4.2 Variance Reduction Techniques 84
4.4.3 Bias 85
4.4.4 Outliers 86
4.4.5 Parameter Estimation 87
4.5 Evaluating and Summarizing the Data 88
4.6 Statistical Inference 90
4.6.1 Inferring the Population Mean 90
4.6.2 Precision and Sample Size 91
4.6.3 Reproducibility and Repeatability 92
4.7 Measurement Automation 95
4.8 Dealing with Feedback and Retransmissions 96
References 97
Part III EXPERIMENTAL LINK-LEVEL EVALUATION
Introduction 101
5 HSDPA Performance Measurements 103
5.1 Mathematical Model of the Physical Layer 104
5.1.1 System Model for the Channel Estimation 106
5.1.2 System Model for the Equalizer Calculation 106
5.2 Receiver 107
5.2.1 Channel Estimation 107
5.2.2 Equalizer 112
5.2.3 Further Receiver Processing 113