UMTS Performance Measurement: A Practical Guide to KPIs for the UTRAN Environment

Preface ix

Acknowledgements xi

1 Basics of Performance Measurement in UMTS Terrestrial Radio Access Network (UTRAN) 1

1.1 General Ideas of Performance Measurement 2

1.1.1 What is a KPI? 4

1.1.2 KPI Aggregation Levels and Correlations 6

1.1.3 Basic Approach to Capture and Filter Performance-Related Data in UTRAN 7

1.1.4 Performance Measurement Definitions of 3GPP 13

1.1.5 User Experience vs. 3GPP Performance Measurement Definitions 16

1.1.5.1 Problems with Registration and Call Setup 17

1.1.5.2 Dropped Calls 19

1.1.5.3 Poor Transmission Speed 20

1.1.5.4 Corrupted Data 25

1.1.6 Basics of PS Call Analysis in UTRAN 27

1.2 Basic Architectural Concept of Performance Measurement Equipment Based on Protocol Analysis 34

1.2.1 Protocol Decoding and Protocol Stacks 37

1.2.2 Diversity Combining and Filtering 39

1.2.3 State Transition Analysis 44

1.3 Aggregation Levels/Dimensions 47

1.3.1 SGSN Dimension 47

1.3.2 MSC Dimension 48

1.3.3 SRNC Dimension 48

1.3.4 DRNC Dimension 48

1.3.5 CRNC Dimension 48

1.3.6 Node B Dimension 49

1.3.7 Cell Dimension 49

1.3.8 Call/Connection Dimension 51

1.3.9 UE Dimensions 51

1.3.10 Radio Bearer/Radio Access Bearer Type Dimensions 52

1.4 Statistics Calculation and Presentation 54

1.4.1 Sampling Period 54

1.4.2 Bins 56

1.4.3 The 95th Percentile 57

1.4.4 Gauges and Distribution Functions 58

2 Selected UMTS Key Performance Parameters 61

2.1 Block Error Rate (BLER) Measurements 61

2.1.1 Uplink Block Error Rate (UL BLER) 62

2.1.1.1 Uplink Transport Channel BLER 62

2.1.1.2 UL BLER per Call 65

2.1.1.3 UL BLER per Call Type 65

2.1.2 Downlink Block Error Rate (DL BLER) 65

2.1.2.1 DL BLER per Call or Service 68

2.1.3 Correlation of BLER and Other Measurements 69

2.2 Radio-Related Measurements 71

2.2.1 Radio Link Quality Parameters and Flow Control in Lub Frame Protocol (FP) 71

2.2.2 NBAP Common Measurements 74

2.2.2.1 Transmitted Carrier Power 76

2.2.2.2 NBAP Common Measurement Enhancements in Release 5 77

2.2.2.3 Received Total Wideband Power 78

2.2.3 NBAP Dedicated Measurements 81

2.2.3.1 Signal-to-Interference Ratio (SIR) 82

2.2.3.2 Signal-to-Interference Ratio Error (SIR Error) 83

2.2.3.3 Uplink SIR Target 85

2.2.3.4 Transmitted Code Power 86

2.2.3.5 Round Trip Time (RTT) 87

2.2.4 RRC Measurements and UE Measurement Abilities 87

2.3 Throughput Measurements 100

2.3.1 RLC Throughput 101

2.3.2 Transport Channel Throughput 102

2.3.3 Packet Switched User Perceived Throughput 112

2.3.4 Application Throughput 114

2.4 Transport Channel Usage Ratio 115

2.5 Primary and Secondary Traffic 118

2.6 Active Set Size Distribution 122

2.7 Soft Handover Success and Failure Analysis 127

2.8 Inter-Frequency Hard Handover Success and Failure Rates 132

2.9 Core Network Hard Handover Success and Failure Rates 137

2.9.1 Intra-MSC and Inter-MSC Hard Handover (3G-3G) 138

2.9.2 3G-2G Inter-RAT Handover for CS and PS Services 143

2.9.2.1 CS 3G-2G Inter-RAT Handover 144

2.9.2.2 PS 3G-2G Inter-RAT Handover 146

2.10 State Transitions and Channel Type Switching 147

2.11 Call Establish Success and Failure Rates 151

2.11.1 RRC Connection Establishment 152

2.11.2 Radio Bearer and Radio Access Bearer Establishment and Release 155

2.12 Call Drop Rates 160

2.13 NBAP Radio Link Failure Analysis and RRC Re-Establishment Success Rate 165

2.14 Cell Matrices 171

2.15 Miscellaneous Protocol Procedures and Events that Indicate Abnormal Behaviour of Protocol Entities on Different Layers 174

2.15.1 Miscellaneous RRC Failure Indications and Ratio KPIs 175

2.15.1.1 RRC UTRAN Mobility Information Failure 175

2.15.1.2 RRC Measurement Control Failure 175

2.15.1.3 RRC Status 175

2.15.1.4 RRC Security Mode Failure 176

2.15.1.5 RRC Transport Format Combination Control Failure 176

2.15.1.6 RRC Paging Response 176

2.15.2 SCCP Failure Analysis 177

2.15.2.1 Connection Refused (CREF) 177

2.15.2.2 Inactivity Check Failure 178

2.15.3 RANAP Failure Analysis 178

2.15.3.1 RANAP Reset Resource 178

2.15.3.2 RANAP Reset 178

2.15.3.3 RANAP Overload 178

2.15.4 NBAP Failure Analysis 178

2.15.5 RLC Acknowledge Mode Retransmission Rate 180

3 Call Establishment and Handover Procedures of PS Calls using HSDPA 181

3.1 HSDPA Cell Set Up 181

3.2 HSDPA Basic Call 182

3.2.1 Call Set Up and Measurement Initialisations 182

3.2.2 Call Release 187

3.3 Mobility Management and Handover Procedures in HSDPA 188

3.3.1 Serving HS-DSCH Cell Change without Change of Active Set 189

3.3.2 Inter-Node B Serving HS-DSCH Cell Change 191

3.3.3 HSDPA Cell Change After Soft Handover 193

Glossary 197

References 205

Index 207