LTE Optimization Handbook

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LTE Optimization Handbook TLA6.0

Document number: LTE/IRC/APP/032749 Document issue: V06.03 / EN

Document status: Approved Standard Data classification: Confidential

Date: 28/Oct/2013

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LTE/IRC/APP/032749 V06.03 / EN Approved Standard 28/Oct/2013 Page 2/290

1 INTRODUCTION

The document is the optimization handbook for the main RF features and related parameters per domain of Alcatel-Lucent LTE release TLA6.0

The procedures detailed in this document can be used to improve the network performance so that it meets contractual and technical objectives prior to a commercial launch. It can also be used in a continuous process as the network evolves due to addition of new cells, increase in traffic load or introduction of new features.

1.1 SCOPE

Main purpose of the document consists of proposing parameter tuning that shall mitigate observed performance degradations.

The following domains are distinguished for parameter tuning: Coverage

Throughput Latency Capacity

Mobility (both connected and idle mode)

The parameters described in this document are related to the Alcatel-Lucent LTE TLA6.0 release.

1.2 AUDIENCE FOR THIS DOCUMENT

The audience of this document is typically involved in following activities: Radio Network Design

Radio Network Optimization First-Of-Arrial Trials

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2 PUBLICATION HISTORY

Version.Ed/

Language Date (dd.mmm.yyyy) Status Name

Reason of changes / short description of significant changes to previous edition

06.00/EN 30.Jan.2013 Draft

MinMin Chen; Yaguang Dong; Peng Xu Creation

06.01/EN 20.Feb.2013 Draft

MinMin Chen; Yaguang Dong; Peng Xu Updated according to TLA6.0.1

06.02/EN 20.May.2013 Approved _preliminary

MinMin Chen; Yaguang Dong; Peng Xu Updated according to TLA6.0.2 &

Reading Cycle Completed

06.03/EN 12.Oct.2013 Approved _Standard

MinMin Chen; Yaguang Dong; Peng Xu Added TM3/8 switching parameter

Updated some description of transmission mode

comparison

Updated default value of parameters according to the latest TLA6.0 MIM default template v34.

Updated according to Reading Cycle Completed.

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10.1.1 dlMCSTransitionTable ... 73 10.1.2 dlSinrThresholdBetweenCLMimoOneLayerAndTxDiv ... 76 10.1.3 dlSinrThresholdBetweenCLMimoTwoLayersAndOneLayer ... 76 10.1.4 dlSinrThresholdBetweenOLMimoAndTxDiv ... 78 10.1.5 dlSINRThresholdbetweenRank1BeamformingAndTM3... 81 10.1.6 dlSINRThresholdbetweenRank2BeamformingAndTM3... 84 10.1.7 deltaSINRforIntermodeSwitch... 88

10.1.8 Downlink Performance Comparison Of Different Transmission Mode ... 89

10.1.8.1 Performance Comparison in CMCC LST DensityUrban Scenario ... 91

10.1.8.2 Performance Comparison in Jinqiao OTA SubUrban Scenario... 94

10.1.8.3 Performance Comparison of Both Scenarios ... 97

10.1.9 AlphaFairnessfactor... 106 10.1.10 DynamicCFIEnabled ... 109 10.1.11 CFI... 110 10.1.12 cfi1allowed ... 110 10.1.13 cfi2allowed ... 111 10.1.14 cfi3allowed ... 111 10.1.15 Measurement Gap... 111 10.2FEATURE LINKED ... 115

10.2.1 T115742- Rel9 DL MU-MIMO BF (TM8 Rank1) ... 115

10.2.1.1 High Level Description and Benefits: ... 115

10.2.1.2 How to activate: ... 116

10.2.1.3 Feature Impacts on KPI’s & Tunable Parameters: ... 116

11 UPLINK THROUGHPUT OPTIMIZATION HINTS ... 118

11.1PARAMETERS OPTIMIZATION FOR IMPROVING UPLINK THROUGHPUT ... 118

11.1.1 uplinkSIRtargetValueForDynamicPUSCHscheduling ... 118

11.1.2 pUSCHPowerControlAlphaFactor ... 121

11.1.2.1 puschpowercontrolalphafactor combination tests ... 124

11.1.2.2 PUSCHPOWERCONTROLALPHAFACTOR COMBINATION TESTS (LIVE NETWORK) .... 132

11.1.3 ulSchedPropFairAlphaFactor ... 133

11.1.4 Measurement Gap ... 134

12 LATENCY OPTIMIZATION HINTS ... 135

12.1PARAMETERS OPTIMIZATION LATENCY ... 135

12.1.1 Test RECOMMENDATION AND results ... 137

12.1.1.1 Attach latency ... 137

12.1.1.2 Attach Latency Results from CMCC LST... 138 12.1.1.3 Quick reminder for isIntraFreqMobilityAllowed and aUGtriggerDelayforRACHmsg4

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12.1.1.4 AUG procedure ... 143

12.1.1.5 aUGtriggerDelayforRACHmsg4 ... 143

12.1.1.6 Idle to active latency ... 144

12.1.1.7 Idle to Active Latency Results From Lab Test ... 145

12.1.1.8 Idle to Active Latency Results From CMCC LST ... 146

12.1.1.9 Quick reminder for isIntraFreqMobilityAllowed and aUGtriggerDelayforRACHmsg4 150 12.1.1.10 Reference of all the SoftWare used in the Platform ... 150

12.1.1.11 Detach latency ... 151

12.1.1.12 Ping Latency results from CMCC LST ... 152

13 CAPACITY OPTIMIZATION HINTS ... 157

13.1PARAMETERS OPTIMIZATION FOR IMPROVING CAPACITY ... 157

13.1.1 Enb CAPACITY CONFIGURATIONS ... 157

13.1.2 alphaFairnessFactor ... 158

13.1.3 UlSchedPropFairAlphaFactor ... 159

13.2UL PHYSICAL CHANNELS CONFIGURATION AND CAPACITY ANALYSIS ... 161

13.2.1 SRS Configuration and Capacity Analysis ... 161

13.2.1.1 The Function of Sounding RS ... 161

13.2.1.2 SRS Configuration in Current Release ... 161

13.2.1.3 Analysis of SRS Configuration Impact on Capacity ... 166

13.2.2 PUCCH Configuration and Capacity Analysis ... 167

13.2.2.1 The Function of PUCCH ... 167

13.2.2.2 PUCCH Configuration in Current Release ... 168

13.2.2.3 Parameters of pucch channel configuration IN TLA3.0/4.x/5.x/6.0 ... 173

13.2.2.4 Analysis of PUCCH Configuration Impact on Capacity ... 175

13.3TLA6.0PUCCH&SRSCONFIGURATIONS AND RECOMMENDATIONS ... 176

14 INTRA LTE MOBILITY OPTIMIZATION HINTS ... 179

14.1NEIGHBOUR CONFIGURATION ... 179

14.1.1 Intra Frequency Neighour Declaration ... 181

14.1.2 Inter Frequency Neighbour Declaration ... 182

14.2MOBILITY PARAMETERS ... 183

14.2.1 Mobility in RRC IDLE MODE ... 184

14.2.1.1 Cell Selection & Reselection... 184

14.2.1.2 QRXLEVMIN ... 187 14.2.1.3 SINTRASEARCH ... 188 14.2.1.4 SNONINTRASEARCH ... 188 14.2.1.5 QHYST ... 189 14.2.1.6 QOFFSETCELL ... 190 14.2.1.7 QRXLEVMINOFFSET ... 190 14.2.1.8 threshServingLow ... 191 14.2.1.9 threshXlow ... 192 14.2.1.10 threshXHigh ... 193 14.2.1.11 TRESELECTIONEUTRAN ... 194 14.2.1.12 TRESELECTIONEUTRASFMEDIUM ... 194 14.2.1.13 TRESELECTIONEUTRASFHIGH ... 195 14.2.1.14 tevaluation ... 196 14.2.1.15 NCELLCHANGEHIGH... 196 14.2.1.16 NCELLChANGEMEDIUM ... 197 14.2.1.17 QHYSTSFHiGH ... 198 14.2.1.18 QHYSTSFMEDIUM ... 198

14.2.2 Mobility in RRC Connected Mode ... 199

14.2.2.1 FILTERCOEFFICIENTRSRP ... 200

14.2.2.2 HYSTERESIS ... 202

14.2.2.3 TIMETOTRIGGER ... 203

14.2.2.4 CELLINDIVIDUALOFFSET... 203

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14.2.2.6 OFFSETFREQ ... 205 14.2.2.7 THRESHOLDEUTRARSRP ... 205 14.2.2.8 THRESHOLD2EUTRARSRP ... 206 14.2.2.9 REPORTINTERVAL ... 207 14.2.2.10 MAXREPORTCELLS ... 207 14.2.2.11 REPORTAMOUNT ... 208

14.2.2.12 Call flow for Inter-eNB mobility, X2 HO – UE in RRC Connected ... 209

14.2.2.13 Call flow for Inter-eNB mobility, S1 HO – UE in RRC Connected... 211

14.2.2.14 Intra LTE Handover Optimization Examples In Field Test ... 212

15 IRAT MOBLILTY OPTIMIZATION HINTS ... 225

15.1INTER-RATMOBILITY STRATEGY ... 225

15.2LTE-UMTSOPTIMIZATION HINTS... 226

15.2.1 Inter- RAT Mobility in RRC Idle Mode ... 227

15.2.1.1 qRxLevMin... 231 15.2.1.2 sNonIntraSearch... 232 15.2.1.3 threshServingLow ... 233 15.2.1.4 threshXLow ... 234 15.2.1.5 tReselectionUtra ... 235 15.2.1.6 TRESELECTIONUTRASFMEDIUM ... 236 15.2.1.7 TRESELECTIONUTRASFHIGH ... 237 15.2.1.8 NCELLCHANGEHIGH ... 237 15.2.1.9 NCELLCHANGEMEDIUM ... 238 15.2.1.10 QHYSTSFHiGH ... 238 15.2.1.11 QHYSTSFMEDIUM ... 239

15.2.2 Field Test Results Of Inter- RAT Mobility in RRC Idle Mode ... 240

15.2.3 Inter-RAT Mobility in RRC Connected Mode ... 242

15.2.3.1 UE measurements needed for PS HO to UTRA-TDD ... 243

15.2.3.2 Redirection To Utran ... 247 15.2.3.3 THRESHOLDEUTRARSRPB2 ... 252 15.2.3.4 THRESHOLDutrarscp ... 252 15.2.3.5 OFFSETFREQUTRA ... 253 15.2.3.6 FILTERCOEFFICIENTOFQUANTITYCONFIGUTRA ... 253 15.2.3.7 HYSTERESIS ... 254 15.2.3.8 TIMETOTRIGGER ... 255 15.2.3.9 REPORTINTERVAL ... 256 15.2.3.10 MAXREPORTCELLS ... 256 15.2.3.11 REPORTAMOUNT ... 257

15.3LTE-GSM MOBILITY OPTIMIZATION HINTS ... 258

15.3.1 IDLE MODE ... 258 15.3.1.1 qRxLevMin... 261 15.3.1.2 SNONINTRASEARCH ... 262 15.3.1.3 THRESHSERVINGLOW ... 263 15.3.1.4 THRESHXLOW ... 264 15.3.1.5 TRESELECTIONGERAN ... 265 15.3.1.6 TRESELECTIONGERANSFMEDIUM ... 266 15.3.1.7 TRESELECTIONGERANSFHIGH ... 266 15.3.1.8 NCELLCHANGEHIGH ... 267 15.3.1.9 NCELLCHANGEMEDIUM ... 268 15.3.1.10 QHYSTSFHiGH ... 268 15.3.1.11 QHYSTSFMEDIUM ... 269 15.3.2 ACTIVE MODE ... 270 15.3.2.1 Redirection to GERAN ... 270

15.3.2.2 Cell Change Order with/without NACC to Geran ... 272

15.3.2.3 THRESHOLDEUTRARSRPB2 ... 275

15.3.2.4 THRESHOLDGERAN ... 276

15.3.2.5 OFFSETFREQGERAN ... 277

15.3.2.6 FILTERCOEFFICIENTOFQUANTITYCONFIGGERAN ... 277

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15.3.2.8 TIMETOTRIGGER ... 279

15.3.2.9 REPORTINTERVAL ... 280

15.3.2.10 MAXREPORTCELLS ... 280

15.3.2.11 REPORTAMOUNT ... 281

16 ABBREVIATIONS AND DEFINITIONS... 281

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LIST OF FIGURES

Figure 8.1-1: CRS boosting Vs. non-boosting test route (Field Results JQHQ OTA–SubUrban) ... 33

Figure 8.1-2: SINR with CRS boosting Vs. without CRS boosting (Field Results JQHQ OTA–SubUrban) ... 33

Figure 8.2-1: UE Drop Position Vs UL coverage (Field Results CMCC LST–Urban) ... 38

Figure 8.2-2: First RRC connection reconfiguration for PUCCH/SRS Position Vs UL coverage (Field Results CMCC LST–Urban) ... 39

Figure 8.2-3: Throughput for single UE vs. Path loss (Lab environment) ... 48

Figure 8.2-4: Cell coverage (idle & connected) vs. qRxlevmin – 2600MHz (Field Results CMCC LST-Urban)... 51

Figure 8.2-5: DL coverage for UE in idle Vs UE in active (Field Results CMCC LST-Urban) ... 52

Figure 8.2-6: qRxLevMin Selection ... 52

Figure 8.2-7: Po_pusch_Nominal Impact ... 55

Figure 8.2-8: Slope - PuschPowerControl vs. uplinkSIRtargetValueForDynamicPUSCHscheduling... 57

Figure 8.3-1: Typical wireless network example ... 58

Figure 8.3-2: Key challenges of wireless network - coverage and capacity ... 58

Figure 8.3-3: One logical cell typical architecture ... 59

Figure 9.1-1: preambleTransMax vs. preambleInitialRceivedTargetPower vs. preambleTransmitPowerStepSize ... 62

Figure 9.1-2: Po_preamble impact on UE Tx Power vs. PL(RA) (TRY1) ... 63

Figure 9.1-3: Po_preamble impact on UE Tx Power vs. PL (RA)... 63

Figure 9.1-4: preambleTransMax vs. preambleInitialRceivedTargetPower vs. preambleTransmitPowerStepSize (example of values) ... 64

Figure 9.1-5: preamble TxPower vs. preambleInitialRceivedTargetPower Vs preamblePowerStepSize (Field Results CMCC LST-Urban) ... 66

Figure 9.1-6: preamble Re-transfer Number vs. preambleInitialRceivedTargetPower Vs preamblePowerStepSize (Field Results CMCC LST-Urban)... 67

Figure 9.1-7: Near Cell RA Success Rate vs. preambleInitialRceivedTargetPower (Field Results CMCC LST-Urban) ... 67

Figure 9.1-8: Parameters dependency and relations ... 69

Figure 9.1-9: RA Success Rate Vs deltaPreambleMsg3 Vs tPCRACHMsg3 (Field Results CMCC LST-Urban) 71 Figure 9.1-10: PUSCH TxPower Vs deltaPreambleMsg3 Vs tPCRACHMsg3 (Field Results CMCC LST-Urban)... 72

Figure 10.1-1: Radio link Quality vs. MCS Robustness vs. Throughput ... 73

Figure 10.1-2: Radio link Quality vs. dlMCSTransition Table vs. Throughput ... 74

Figure 10.1-3: Dl Sinr Threshold Example ... 77

Figure 10.1-4: CL 2Layer-1Layer SNR Switch Threshold: 10 dB (purple) vs. 12 dB (blue) AWGN (Lab results VzW) ... 78

Figure 10.1-5: CL 2Layer-1Layer SNR Switch Threshold: 10 dB (purple) vs. 12 dB (blue) EPA 5Hz, Medium Correlation (Lab Results VzW)... 78

Figure 10.1-6: Dl Sinr Threshold Example ... 79

Figure 10.1-7: dl SINR Threshold for TM switching driver test route (CMCC LST urban) ... 80

Figure 10.1-8: OL 2Layer-TxDiv SINR Switch Threshold vs Phy average throuthput (CMCC LST Density urban) 81 Figure 10.1-9: dlSINRThreshold for TM3/7 Switch vs. PDCP average throughput (CMCC LST Density urban) 83 Figure 10.1-10: dlSINRThreshold for TM3/7 Switch vs. 2 codewords rate (CMCC LST Density urban) ... 83

Figure 10.1-11: dlSINRThreshold for TM3/7 Switch vs. TM7 rate (CMCC LST Density urban) ... 84

Figure 10.1-12: Test road path for TM3/8 switching (CMCC LTE TDD pre-commercial deployment Qingdao -Density urban) ... 86

Figure 10.1-13: PDCP average throughput TM3 vs. TM8 (CMCC LTE TDD pre-commercial deployment Qingdao -Density urban) ... 86

Figure 10.1-14: PDCP average throughput TM3 vs. TM3/8 switching (CMCC LTE TDD pre-commercial deployment Qingdao -Density urban) ... 87

Figure 10.1-15: dlSINRthreshold for TM3/8 switching vs. PDCP average throughput (CMCC LTE TDD pre-commercial deployment Qingdao -Density urban) ... 88

Figure 10.1-16: dlSINRthreshold for TM3/8 switching vs. PDCP average throughput (CMCC LTE TDD pre-commercial deployment Qingdao -Density urban) ... 88

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LTE/IRC/APP/032749 V06.03 / EN Approved Standard 28/Oct/2013 Page 10/290 Figure 10.1-17: Test route path for TM performance comparison (site Lvkai in CMCC LST density

urban) 90

Figure 10.1-18: Test route path for TM performance comparison (OTA in Jinqiao_Suburban) ... 91

Figure 10.1-19: SINR vs. Avg. Throughput of TM2/3/7/8 (site Lvkai in CMCC LST density urban) ... 92

Figure 10.1-20: SINR vs. MCS of TM2/3/7/8 (site Lvkai in CMCC LST density urban)... 92

Figure 10.1-21: SINR vs. BLER of TM2/3/7/8 (site Lvkai in CMCC LST density urban) ... 93

Figure 10.1-22: SINR vs. CQI_0 of TM2/3/7/8 (site Lvkai in CMCC LST density urban) ... 93

Figure 10.1-23: SINR vs. Avg. Throughput of TM2/3/7/8 (OTA in Jinqiao suburban) ... 95

Figure 10.1-24: SINR vs. MCS of TM2/3/7/8 (OTA in Jinqiao suburban) ... 95

Figure 10.1-25: SINR vs. BLER of TM2/3/7/8 (OTA in Jinqiao suburban) ... 96

Figure 10.1-26: SINR vs. CQI_0 of TM2/3/7/8 (OTA in Jinqiao suburban) ... 96

Figure 10.1-27: SINR vs. Avg. Throughput of TM3 in both scenarios ... 98

Figure 10.1-28: SINR vs. MCS of TM3 in both scenarios ... 98

Figure 10.1-29: SINR vs. BLER of TM3 in both scenarios ... 99

Figure 10.1-30: SINR vs. CQI_0 of TM3 in both scenarios ... 99

Figure 10.1-43: UEs’ distribution illustration ... 107

Figure 10.1-44: alphaFairnessFactor Change Impact with UE in different condition... 108

Figure 10.1-45: alphaFairnessFactor Change Impact – further details ... 109

Figure 10.1-46: Measurement Gap on DL and UL transmissions for TDD ... 112

Figure 10.1-47: Test road path for MG comparison ... 113

Figure 10.2-1: MU-MIMO Principle ... 115

Figure 11.1-1: Impact of PUSCH Power for ul_PUSCH_SIRtarget (Field Results CMCC LST-Urban)... 120

Figure 11.1-2: Impact of the Neighbor Cell IoT for ul_PUSCH_SIRtarget (Field Results CMCC LST-Urban)... 121

Figure 11.1-3: Impact of the pUSCHPowerControlAlphaFactor =1.0 in MCS usage. ... 123

Figure 11.1-4: Impact of the pUSCHPowerControlAlphaFactor =0.8 in Throughput per RB ... 124

Figure 11.1-5: Impact of the pUSCHPowerControlAlphaFactor =0.7 in Throughput per RB. ... 124

Figure 11.1-6: Set 1 Result ... 126

Figure 11.1-7: Set 1UL Throughput & UE TX Power vs. Path loss ... 127

Figure 11.1-8: SIR Target for theoretical assumptions with different alpha factor values ... 128

Figure 11.1-9: UL SIR Target for theoretical assumptions with different alpha factor values ... 128

Figure 11.1-10: Different alpha factor comparison (Throughput, PRB’s, SINR & PUSCH SINR Target) ... 129

Figure 11.1-11: UL Throughput & UE TX Power vs. Path loss alpha factor 0.7 & 1 with set 3 ... 130

Figure 11.1-12: UL Throughput & UE TX Power vs. Path loss for alpha factor 0.7 for all sets ... 131

Figure 11.1-13: UL Throughput vs. Path loss for set1 & set3 with alpha factor 0.7 and 1 ... 132

Figure 11.1-14: UE TX Power vs. Path loss for set1 & set3 with alpha factor 0.7 and 1 ... 132

Figure 11.1-15: Impact of the ulSchedPropFairAlphaFactor ... 133

Figure 12.1-1: Example for IMSI attach procedure (with authentication) ... 137

Figure 12.1-2: Example for GUTI attach procedure (no authentication) ... 138

Figure 12.1-3: Initial Attach latency comparison overview ... 139

Figure 12.1-4: Initial Attach latency and ratio (with authentication and Identity) in CMCC LST ... 139

Figure 12.1-5: Initial attach latency example (without authentication and Identity) in CMCC LST ... 140

Figure 12.1-6: Initial Attach procedure and latency example (with authentication and Identity) ... 140

Figure 12.1-7: aUGtriggerDelayforRACHmsg4 Vs. Attach latency ... 140

Figure 12.1-8: isIntraFreqMobilityAllowed Vs. Attach latency ... 141

Figure 12.1-9: Authentication configuration in MME... 142

Figure 12.1-10: AUG flow chart ... 143

Figure 12.1-11: Idle to active message chart ... 145

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Figure 12.1-13: Idle to active latency results from CMCC LST ... 147

Figure 12.1-14: aUGtriggerDelayforRACHmsg4 vs. latency ... 148

Figure 12.1-15: isIntraFreqMobilityAllowed vs. latency ... 148

Figure 12.1-16: SINR vs. latency ... 149

Figure 12.1-17: Idle to activity message chart and latency ... 149

Figure 12.1-18: Authentication configuration in MME ... 150

Figure 12.1-19: No RF parameter optimization possible for detach latency! ... 151

Figure 12.1-20: Non pre-scheduled and pre-scheduled Ping latencies with 32 byte payload (CMCC LST-Urban) ... 152

Figure 12.1-21: Non-scheduled and pre-scheduled Ping latencies with 1400 byte payload (CMCC LST-Urban)... 153

Figure 12.1-22: Overall Results (CMCC LST-Urban) ... 154

Figure 12.1-23: Pre-scheduled vs. Non Scheduled Ping latency (32 Bytes) in Low SNR and High SNR (CMCC LST-Urban) ... 155

Figure 12.1-24: Pre-scheduled vs. Non Scheduled Ping latency (1432 Bytes) in Low SNR and High SNR (CMCC LST-Urban) ... 156

Figure 13.2-1: SoundingRS-UL-Config information element ... 162

Figure 13.2-2: SRS frequency allocation example ... 163

Figure 13.2-3: SRS capacity calculation example ... 166

Figure 13.2-4: PUCCH with P-CQI capacity calculation example ... 176

Figure 14.1-1: Coverage (Best Cell ID) analysis of South Pudong road area in CMCC LST – done by ARFCC team ... 180

Figure 14.1-2: X2-Link access ... 181

Figure 14.1-3: LTE Intra Frequency Neighbour list ... 182

Example below in Figure 14.1-4 shows the sector LST008_1 have Intra neighbours of sector LST008_2 and LST008_3, etc. ... 182

Figure 14.1-5: LTE Inter Frequency Neighbour list ... 183

Figure 14.2-1: LTE to LTE Mobility – Measurement phase (RSRP vs. Time) ... 185

Figure 14.2-2: LTE to LTE Mobility – Ranking Phase... 185

Figure 14.2-3: LTE to LTE Mobility – Decision Phase (RSRP vs. Time) ... 186

Figure 14.2-4: LTE to LTE Mobility – Measurement phase (RSRP vs. Time) ... 187

Figure 14.2-5: LTE to LTE Mobility – Handover cases ... 199

Figure 14.2-6: Theoretical view ... 201

Figure 14.2-7: filterCoefficientRSRP - Theoretical comparison (Simulation Analysis) ... 201

Figure 14.2-8: Call flow for Inter-eNB mobility, X2 HO – UE in RRC Connected (1) ... 209

Figure 14.2-9: Call flow for Inter-eNB mobility, X2 HO – UE in RRC Connected (2) ... 210

Figure 14.2-10: Call flow for Inter-eNB mobility, S1 HO – UE in RRC Connected (1) ... 211

Figure 14.2-11: Call flow for Inter-eNB mobility, S1 HO – UE in RRC Connected (2) ... 212

Figure 14.2-12: Test route and RSRP before optimization ... 213

Figure 14.2-13: UE Signalling and Events in target cell before optimization ... 213

Figure 14.2-15: UE Signalling and Events in target cell before optimization ... 215

Figure 14.2-16: No measconfig received when UE attach in source cell before optimization ... 215

Figure 14.2-17: RSRP became better after optimization ... 216

Figure 14.2-18: UE successfully HO to target cell after optimization ... 216

Figure 14.2-19: Detail of measConfig message received after optimization ... 217

Figure 14.2-21: UE Signalling and Events in source cell before optimization ... 218

Figure 14.2-22: Detail signalling message when no measurement report before optimization ... 219

Figure 14.2-23: RSRP became better after optimization ... 220

Figure 14.2-24: source eNB received MR and UE successfully HO to target cell after optimization ... 220

Figure 14.2-25: Detail of measConfig message received in source cell after optimization ... 221

Figure 14.2-27: UE Signalling and Events in source cell before optimization ... 222

Figure 14.2-28: Detail signalling message of measConfig and received measurement report in source cell before optimization ... 223

Figure 14.2-29: HO ping pong area between cell_121 and cell_108 (CMCC LST-Density urban) ... 224

Figure 15.1-1: 2G/3G/LTE RAT selection example when multimode UE switch on ... 225

Figure 15.1-2: LTE TDD/Utran TDD RAT coverage gap example ... 226

Figure 15.2-1: LTE to UTRAN mobility in the context of IRAT mobility ... 227

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Figure 15.2-3: UE rules follow-up... 229

Figure 15.2-4: LTE to UTRAN Mobility – (RSRP vs. Time) measurement phase ... 230

Figure 15.2-5: LTE to UTRAN Mobility – Algorithm Cell Reselection toward lower priority UTRAN Cell... 231

Figure 15.2-6: LTE to UTRAN Mobility – (RSRP vs. Time) Decision Phase ... 231

Figure 15.2-7: LTE TDD/Utran TDD IRAT cell reselection driver test route ... 240

Figure 15.2-8: Detail signalling and events example of LTE TDD/Utran TDD IRAT cell reselection ... 241

Figure 15.2-9: Events state machine ... 243

Figure 15.2-10: UE measurements needed for PS HO to UTRA-TDD ... 243

Figure 15.2-11: Call flow for PS HO – Preparation phase ... 244

Figure 15.2-12: Call flow for PS HO – Execution phase ... 246

Figure 15.2-13: PS HO to UTRA-TDD - End-to-End call flows ... 247

Figure 15.2-14: LTE to UTRAN Mobility – Redirection Execution ... 247

Figure 15.2-15: RAT frequency with highest cellReselectionPriority is chosen for redirection ... 248

Figure 15.2-16: RRC Connection Release with Redirection Info from EUTRAN to UTRAN ... 249

Figure 15.2-17: Inter RAT threshold for event B2 ... 249

Figure 15.2-18: Call flow for redirection from EUTRAN to UTRAN-Overview ... 250

Figure 15.2-19: Call flow for redirection from EUTRAN to UTRAN-Description ... 251

Figure 15.3-1: Reselection from eUTRAN to GERAN ... 258

Figure 15.3-2: LTE to GERAN Mobility – HO to GERAN cell ... 259

Figure 15.3-3: LTE to GERAN Mobility (RSRP vs. Time) – Cell Reselection – Measurement phase ... 260

Figure 15.3-4: LTE to GERAN Mobility – Cell Reselection toward lower priority GERAN cell ... 260

Figure 15.3-5: LTE to GERAN Mobility (RSRP vs. Time) – Cell Reselection – Decision phase ... 261

Figure 15.3-6: Inter RAT threshold for event B2 ... 271

Figure 15.3-7: Call Flow for Redirection to Geran ... 272

Figure 15.3-8: Serving Radio Condition and UE Measurement Configurations ... 273

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LIST OF TABLES

Table 6-1: Parameters impacting UL coverage ... 18

Table 6-2: Parameters impacting DL coverage ... 19

Table 6-3: Parameters impacting attach/detach procedures ... 20

Table 6-4: Parameters impacting DL throughput ... 22

Table 6-5: Parameters impacting UL throughput... 23

Table 6-6: Parameters impacting control plane latency... 24

Table 6-7: Parameters impacting eNB Capacity ... 25

Table 6-8: Parameters impacting measurements for intra-LTE mobility ... 26

Table 6-9: Parameters impacting measurements for inter-frequency (idle mode) ... 26

Table 6-10: Parameters impacting measurements for inter-frequency (active mode) ... 26

Table 6-11: Parameters impacting LTE – UMTS Inter-Frequency (Idle Mode) ... 27

Table 6-12: Parameters impacting LTE – UMTS Inter-Frequency (Active Mode) ... 28

Table 6-13: Parameters impacting LTE – GSM (Idle Mode) ... 28

Table 6-14: Parameters impacting LTE – GSM (Active Mode) ... 29

Table 7-1: TLA6.0 New Features ... 30

Table 8-1: In the trial mode, the default setting for parameter referenceSignalPower ... 32

Table 8-2: The factor m for TDD_i ... 34

Table 8-3: 2×20W RRH Power Recommended Values in TM2/3/4 (10 MHz bandwidth) ... 40

Table 8-6: 8×5W RRH Power Recommended Values in TM2/3 (10 MHz bandwidth)... 42

Table 8-9: 8×5W RRH Power Recommended Values in TM7 (10 MHz bandwidth) ... 43

Table 8-15: UL 2.6GHz ... 47

Table 8-16: Path Loss & UL Cell Range in Dense Urban in Car (Field Results CMCC LST) ... 47

Table 8-17: DL Cell Range in Dense Urban in Car (Field Results CMCC LST) ... 47

Table 8-18: Parameters to activate feature ... 59

Table 8-19: Tuneable parameters ... 60

Table 9-1 K_PUSCH for TDD configuration 0-6 ... 70

Table 10-1: Examples of threshold tuning for a 10MHz band (academic only, not applied in any trial /project). ... 75

Table 10-2: Theory Assumption on CFI Tuning ... 110

Table 10-3: Measurement Gap Pattern configurations ... 111

Table 10-4: MG impact on DL&UL throughput performance of UL/DL config2/7 (CMCC TDD LTE pre-commercial deployment Qingdao - Urban) ... 114

Table 10-5: HO delay test results w/wo MG enabled (CMCC TDD LTE pre-commercial deployment Qingdao - Urban)... 114

Table 10-6: Test SW configuration Reference ... 115

Table 10-7: Parameters to activate feature ... 116

Table 10-8: Tuneable parameters ... 117

Table 11-1: uplinkSIRtargetValueForDynamicPUSCHscheduling vs. PUSCHPowerControlAlphaFactor... 119

Table 11-2: Different Set’s Combinations ... 125

Table 12-1: SW Reference ... 151

Table 12-2: Ping Latency for 32 Bytes with and without prescheduled for U-plane latency (CMCC LST-Density urban) ... 152

Table 12-3: Test SW configuration Reference ... 156

Table 13-1: TLA6.0 Capacity figures ... 158

Table 13-2: TLA6.0 SRS bandwidth configuration ... 164

Table 13-3: Power limitation of different SRS bandwidth configuration ... 165

Table 13-4: SRS subframe configuration... 165

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Table 13-6: Supported PUCCH formats ... 167

Table 13-7: PUCCH common parameters ... 169

Table 13-8: PUCCH dedicated parameters ... 169

Table 13-9: SR configuration parameters ... 170

Table 13-10: SR configuration Index ... 170

Table 13-11: PUCCH CQI/PMI report configuration Index ... 171

Table 13-12: PUCCH RI report configuration Index ... 171

Table 13-13: SR configuration parameters ... 172

Table 13-14: PUCCH Format 1a/1b configuration parameters ... 172

Table 13-15: Per-UE Parameters from LUTs for TDD ... 173

Table 13-16: Per-Cell Parameters from MIM and LUTs since TLA3.0 ... 173

Table 13-17: Additional Per-Cell and CQI related parameters to pre-calculate LUTs for TDD ... 175

Table 13-18: Maximum number of users supported according to PUCCH formats ... 175

Table 13-19: Uplink control channel/signal LookUpTable-Index0 ... 177

Table 14-1: Some Mobility parameters ... 184

Table 15-1: IRAT cell reselection between LTE TDD & Utran TDD test results in CMCC LST (Density Urban)... 241

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3 REFERENCE DOCUMENTS

Ref. Document Number Title

[1] LTE/IRC/APP/031548 LPUG TLA6.0

[2] LTE/IRC/APP/032749 TLA5.1 Optimization Handbook

[3] MIM 15.1.3 template _{– W1339.5 – V34} TLA6.0.2-MIM15.1.3-template-v34.xtpl

[4] LTE/SYS/APR/034643 _{v01.07 draft} FTS for FRS T115590 Support of Multi-RRH per Cell (One Logic _{Cell) for Indoor Coverage}

4 RELEASE RELATED DOCUMENTS

Ref. Document Number Title

[1] LTE/IRC/APP/032318 LA5.0 Service Performance Handbook

[2] LTE/IRC/APP/031966 LA5.0 Migration - QoS and Stability Monitoring Handbook

[3] LTE/IRC/APP/031688 LA5.0 Engineering Toll Recommendation and Strategy

[4] LTE/IRC/DJD/034923 LTE NEA TestPlan TLA6.0_V03.01

[5] LTE/IRC/APP/032278 LA5.0 LTE Optimisation Troubleshooting Handbook

[6] LTE/IRC/APP/034221 LA5.0 LIMO Executive Report User Guide

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5 PROCESS AND METHODOLOGY

5.1 TOOLS AND RESOURCES

Tools used for the Network Optimization are described in the “LTE Engineering Tool Recommendation and Strategy” document.

5.2 OPTIMIZATION TOOLS

A set of tools are needed to carry out the optimization objectives:

Simulation Tool for RF design: Alcatel-Lucent uses A9155. Used for antenna change validation and RF analysis. There must be consistency with the methods used by the customer so it is possible to use their solution if it has been validated by Alcatel-Lucent teams.

Data Acquisition Platform (DAP): currently Nixt Platform, composed of JSDU Nixt E6474A, W1314A receiver and 1 to 4 test mobiles.

Tests Mobiles: typically Hisilicon, Qualcomm, Innofidei. Also IPW (Altair) or Sequans UEs. Post processing platform (PPP): CDS (Hugeland) which allow post-processing UE DT trace or

Gladiator which allow automatic and customized KPI generation, built-in failure characterization, as well as UE and Call Trace synchronization capabilities (for a deeper and accurate analysis).

For enhanced troubleshooting, the usage of a protocol analyzer (Agilent DNA, Nethawk, etc ) may be required, in particular to monitor the S1 and X2 interfaces.

Project Database: For a correct follow-up of all the optimization activities it is mandatory to have a common and unique project information system (Project Database) which contains the following information:

Site configuration (geographical coordinates, antenna height/azimuth/tilt) Site issues

Updated operations plan Implemented/Planned Changes

Metrics: performance KPI, outage times, workload, delays, escalated issues etc. Work Orders and implementation delays

Reporting templates Equipment tracking List of raised ARs

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6 OPTIMIZATION PARAMETERS OVERVIEW

This chapter is intended to present various parameters existing in ALU RAN, grouped per main area of interest in trials and network deployments. Grouping was made such that it reflects various types of tests that are being performed during trials and KPIs tests that might as well be addressed during trials and network deployment.

Parameters have been split by following domains: Coverage Attach /Detach Throughput Latency Capacity Mobility

Due to the wide scope of mobility, the parameters impacting mobility have been further divided in: LTE – LTE mobility

LTE – UTRA TDD (TD-SCDMA) mobility LTE - GSM mobility

Inside each group, parameters are ordered by the most important and relevant for optimization activities. They should be optimized in case of strong constraints for performance (very demanding KPI, strong competition).

To each parameter is associated a recommended value that can be obtained from [1] for parameters that have not been yet optimized in field activities. The parameters for which a different, optimized, value have been obtained in various field tests, have recommended values specified in the corresponding paragraphs along with some precisions about the conditions in which the optimized value have been obtained (cluster, load).

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6.1 PARAMETERS IMPACTING COVERAGE

The parameters of TLA6.0 release having an impact on coverage are presented in the table below. Most often the coverage is determined by UL link thus for optimizing coverage it is needed to optimize levels of UL power.

Below one can find the parameters commented and reviewed for DL & UL Coverage.

Object Name Recommended Value

ULPowerControlConf pUSCHPowerControlAlphaFactor 0.8

ULPowerControlConf p0NominalPUSCH Check Recommendation

EnbRadioConf uplinkSIRtargetValueForDynamicPUSCH_scheduling Check Recommendation

EnbRadioConf sEcorrInit 0

EnbRadioConf sEcorrStepForLowerBler Check Recommendation

EnbRadioConf sEcorrStepForHigherBler Check Recommendation

EnbRadioConf ulSyncSINRsyncToOOSTreshold Check Recommendation

EnbRadioConf ulSyncSINROOStoSyncTreshold Check Recommendation

CellSelectionReselectionConf qRxLevMin Check Recommendation

ULPowerControlConf deltaFPUCCHFormat1 deltaFm2

ULPowerControlConf sIRTargetforReferencePUCCHFormat 0.0 [dB]

ULPowerControlConf minSIRtargetForFractionalPowerCtrl 0.0 [dB]

ULPowerControlConf maxSIRtargetForFractionalPowerCtrl 22.0 [dB]

ULPowerControlConf pathLossNominal Check Recommendation

ULPowerControlConf p0NominalPUCCH -100 [dBm]

Table 6-1: Parameters impacting UL coverage

Here, parameters for PRACH & PUCCH power control are optional.

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CellSelectionReselectionConf qRxLevMin Check _{Recommendation}

PowerOffsetConfiguration referenceSignalPower Check _{Recommendation}

PowerOffsetConfiguration primarySyncSignalPowerOffset Check _{Recommendation}

PowerOffsetConfiguration secondarySyncSignalPowerOffset Check _{Recommendation}

PowerOffsetConfiguration pBCHPowerOffset Check _{Recommendation}

PowerOffsetConfiguration pDCCHPowerOffsetSymbol Check _{Recommendation}

PowerOffsetConfiguration pCFICHPowerOffset Check _{Recommendation}

PowerOffsetConfiguration pHICHPowerOffset Check _{Recommendation}

PowerOffsetConfiguration pbOffsetPdsch Check _{Recommendation}

PowerOffsetConfiguration paOffsetPdsch Check _{Recommendation}

LteCell cellDLTotalPower Check _{Recommendation}

PowerOffsetConfiguration phichResource one

CellL1L2ControlChannelsConf dlTargetSINRTableForPDCCH [10.50,11.00,10.50,0.0 0,0.00,0.00,13.50,13.5 0,10.50,10.50,5.00,6.0 0,5.00,0.00,0.00,0.00, 7.00,7.00,5.00,5.00,1. 75,2.50,1.75,0.00,0.00 ,0.00,3.00,3.00,1.75,1. 75,-0.50,1.00,-0.50,0.00,0.00,0.00,1. 50,1.50,-0.50,-0.50]

CellL1L2ControlChannelsConf pdcchAggregationLevelForCRNTIGrantsInC_{ommonSearchSpace} 8

CellL1L2ControlChannelsConf pdcchAggregationLevelForUESearchSpace 4

UeTimers n310 n20

UeTimers t310 ms2000

Table 6-2: Parameters impacting DL coverage

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LTE/IRC/APP/032749 V06.03 / EN Approved Standard 28/Oct/2013 Page 20/290 Network performance can be evaluated by some measures implying attach and detach procedures (e.g. attach time, detach time, attach success rate). The parameters impacting attach, detach procedures are listed in the table below.

CellRachConf preambleInitialReceivedTargetPower dBm-94

CellRachConf preambleTransmitPowerStepSize dB4

ULPowerControlConf deltaPreambleMsg3 12

CellRachConf tPCRACHMsg3 4dB

CellRachConf preambleTransMax n8

LteCellTDD spare4 3868311659 (bit#0~#15 _value=49259)

CellRachConfTDD maxHARQmsg3Tx 4

CellRachConf maximumNumberOfDLTransmisionsRACH_Message4 4

CellRachConf rootSequenceIndex

Set according to

prachConfigurationIndex , also the Network Planning

CellRachConf zeroCorrelationZoneConfig 12

CellRachConfTDD prachConfigurationIndex Set according to PRACH _format

CellRachConf prachFrequencyOffset Set according to PRACH format, also the

capacity

CellRachConf numberOfRAPreambles 56

CellRachConf macContentionResolutionTimer Sf64

CellRachConf pRACHDetectFalseAlarmProb 0dot1

CellRachConfTDD receptionOfMsg1Timer 30

UeTimers n310 n20

UeTimers t310 ms2000

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6.3 PARAMETERS IMPACTING THROUGHPUT

The parameters that can impact the throughput, both on UL and on DL, are listed in the table below. On DL the throughput is most influenced by the type of antenna system that is being used/selected wile on UL by the required quality of the received signal, which forces higher powers of PUSCH channel. Note that some parameters can increase the DL throughput while decreasing the UL throughput in the meantime due to the asymmetry of TDD LTE. These parameters are marked by a ‘*’.

Moreover, Some TM7/TM8 related parameters used for 8 Antennas are listed as well, because TM7 can improve cell-edge users’ performance and TM8 can improve both near-cell and cell-edge users’ performance; IRC related parameter is also listed since it can improve the UL performance.

EnbRadioConf dlMCSTransitionTable Check table

DownlinkMimo dlSinrThresholdBetweenCLMimoOneLaye_rAndTxDiv -10.0

DownlinkMimo dlSinrThresholdBetweenCLMimoTwoLay_{ersAndOneLayer} 12.0

DownlinkMimo dlSinrThresholdBetweenOLMimoAndTxDi_v Check Recommendation

LteCellTDD* subframeAssignment Set according to _{customer strategy}

LteCellTDD specialSubframePatterns Set according to _{customer strategy}

CellL2DLConf AlphaFairnessfactor 1.0

CellL1L2ControlChannelsConf DynamicCFIEnabled ture

CellL1L2ControlChannelsConf cFI 3

CellL1L2ControlChannelsConf cFI1Allowed True

CellL1L2ControlChannelsConf cFIThreshold1 2

CellL1L2ControlChannelsConf cFIThreshold2 6

CellL1L2ControlChannelsConf cFIIncreaseTimer 5

CellL2DLConfTDD dlBasicSchedulingMode PF

LteCellTDD transmissionMode Check Recommendation

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UEAdaptiveBeamForming uLCESINRThresholdBetweenTxDivAndBe_{amFormingIntraTm7} -17.0

UEAdaptiveBeamForming sinrOffsetForBeamformingCQICompensa_tion 3.0

AdaptiveTransmissionModeSwit

ch dlSINRThresholdbetweenRank1BeamformingAndTM3 Check Recommendation AdaptiveTransmissionModeSwit

ch dlSINRThresholdbetweenRank2BeamformingAndTM3 Check Recommendation AdaptiveTransmissionModeSwit

ch deltaSINRforIntermodeSwitch 3.0

UEAdaptiveBeamFormingTM8 beamFormingAlgoRank1 COM-EBB

UEAdaptiveBeamFormingTM8 beamFormingAlgoRank2 SU-BF-RANK2-COMEBB

UEAdaptiveBeamFormingTM8 dlSinrThresholdBetweenRank1BeamFor_{mingAndRank2BeamForming} 0.0

UEAdaptiveBeamFormingTM8 dlSinrThresholdBetweenTxDivAndRank1_BeamForming 0.0

UEAdaptiveBeamFormingTM8 rIThresholdBetweenRank1AndRank2 0.6

UEAdaptiveBeamFormingTM8 sinrOffsetForBeamformingPMICQI 0.0

UEAdaptiveBeamFormingTM8 sinrOffsetForBeamformingTxDivCQI 0.0

UEAdaptiveBeamFormingTM8 sinrOffsetForRank1AndRank2CW0 0.0

UEAdaptiveBeamFormingTM8 sinrOffsetForRank2CW0AndCW1 0.0

UEAdaptiveBeamFormingTM8 uLCESINRThresholdBetweenRank1BeamF_{ormingAndRank2BeamForming} -51.2

UEAdaptiveBeamFormingTM8 uLCESINRThresholdBetweenTxDivAndRa_{nk1BeamForming} -51.2

UEAdaptiveBeamFormingTM8 blerThresholdBetweenRank1BeamFormi_{ngAndRank2BeamForming} 1.0

UEAdaptiveBeamFormingTM8 blerThresholdBetweenTxDivAndRank1Be_amForming 0.8

UEAdaptiveBeamFormingTM8 pmiRIReportR9 false

CellL1ULConfTDD cqiReportingModeAperiodic rm30

CellL1ULConfTDD tddAckNackFeedbackMode multiplexing

Table 6-4: Parameters impacting DL throughput

EnbRadioConf uplinkSIRtargetValueForDynamicPUSCHs_cheduling Check Recommendation

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CellL2ULConf ulSchedPropFairAlphaFactor 0.5

EnbRadioConf ulMCSTransitionTableForLargePUSCHGra_nts Check table

EnbRadioConf ulMCSTransitionTableForSmallPUSCHGra_nts Check table

EnbRadioConfTDD mCScorrectionForIRC 0.0

ULPowerControlConf minSIRtargetForFractionalPowerCtrl 0.0 [dB]

ULPowerControlConf maxSIRtargetForFractionalPowerCtrl 19.0 [dB]

ULPowerControlConf pathLossNominal Check Recommendation

ULPowerControlConf p0NominalPUSCH Check Recommendation

Table 6-5: Parameters impacting UL throughput

6.4 PARAMETERS IMPACTING LATENCY

Latency is generally considered either as control plane latency or as user plane latency. Control plane latency involves the network attachment operation while user plane latency only considers the latency of packets while UE is in connected state.

Parameters impacting control plane latency (attachment operation) and user plane latency are given in the tables below.

Most of parameters impacting attachment operations are higher limits of various processes taking place during attachment procedure. The impact of such limits on the value of control plane latency is not significant.

CellRachConf preambleInitialReceivedTargetPower dBm-94 CellRachConf preambleTransMax n8 CellRachConf preambleTransmitPowerStepSize dB4 EnbRadioConf aUGtriggerDelayforRACHmsg4 5 CellRachConf macContentionResolutionTimer Sf64 CellRachConfTDD maxHARQmsg3Tx 4 CellRachConf maximumNumberOfDLTransmisionsRACHMessage4 4

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LteCellTDD spare4 3868311659 (bit#0~#15

value=49259) Table 6-6: Parameters impacting control plane latency

6.5 PARAMETERS IMPACTING CAPACITY

The parameters impacting capacity are listed in the table below.

CellL2DLC onf alphaFairnessFactor 1 CellL2ULC onf ulSchedPropFairAlphaFa ctor 0.5 CellL1L2Co ntrolChann elsConf dlTargetSINRTableForPD CCH [10.50,11.00,10.50,0.00,0.00,0.00,13.50,13.50,10.50,10.50,5 .00,6.00,5.00,0.00,0.00,0.00,7.00,7.00,5.00,5.00,1.75,2.50, 1.75,0.00,0.00,0.00,3.00,3.00,1.75,1.75,-0.50,1.00,-0.50,0.00,0.00,0.00,1.50,1.50,-0.50,-0.50] CellL1L2Co ntrolChann elsConf pdcchAggregationLevelF orCRNTIGrantsInCommo nSearchSpace 8 CellL1L2Co ntrolChann elsConf pdcchAggregationLevelF orNonCRNTIGrantsInCom monSearchSpace 8 CellL1L2Co ntrolChann elsConf pdcchAggregationLevelF orUESearchSpace 4 CellL1L2Co ntrolChann elsConf sINRThresholdBetweenA L4andAL8 30.0 CellL2DLC onfTDD dlBasicSchedulingMode PF CellL2ULC onfTDD ulBasicSchedulingMode PF CellL2DLC onfTDD maxNumberOfRBsPerUE 100 CellL2DLC onfTDD maxGrantedUsers 9 CellL2DLC onf maximumFSSUsers 32 CellL2DLC

onf maximumUsersInACQIListFromDLScheduler 32 CellL2ULC

onf

aperiodicCQIuserListMax

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LTE/IRC/APP/032749 V06.03 / EN Approved Standard 28/Oct/2013 Page 25/290 CellL2ULC

onf maxNbrULFSUsers 32

CellL1ULC

onf uplinkControlChannelLUTindex 0 Table 6-7: Parameters impacting eNB Capacity

6.6 PARAMETERS IMPACTING MOBILITY

Mobility in LTE includes mobility during idle states and during active states. Mobility can involve several technologies and several frequencies.

Note: Measurement Gap feature parameters can impact the mobility parameters considered through the quality of measurement performed.

6.6.1 LTE – LTE MOBILITY

Because measurements are somehow a common part of various types of mobility, in the table below are listed the parameters impacting measurement process for intra-LTE mobility.

CellSelectionReselectionConf qRxLevMin -140 CellSelectionReselectionConf sIntraSearch 62 CellSelectionReselectionConf qRxlevminoffset 2 CellSelectionReselectionConf qHyst dB2 CellReselectionConfLte tReselectionEUTRAN 2 LteNeighboringCellRelation qoffsetCell dB0 RrcMeasurementConf filterCoefficientRSRP Fc8

LteSpeedDependentConf tReselectionEutraSfMedium oDot5

LteSpeedDependentConf tReselectionEutraSfHigh oDot25

SpeedStateEvalConf tEvaluation S30 SpeedStateEvalConf nCellChangeHigh 12 SpeedStateEvalConf nCellChangeMedium 4 SpeedStateEvalConf qHystSfHigh dB-6 SpeedStateEvalConf qHystSfMedium dB-6 ReportConfigEUTRA Hysteresis 2 ReportConfigEUTRA timeToTrigger ms100 LteNeighboringCellRelation cellIndividualOffset dB0 ReportConfigEUTRA eventA3Offset 2 LteNeighboringFreqConf offSetFreq dB0

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ReportConfigEUTRA reportInterval ms240

ReportConfigEUTRA maxReportCells Check Recommendation

ReportConfigEUTRA reportAmount r8

Table 6-8: Parameters impacting measurements for intra-LTE mobility

CellSelectionReselectionConf qRxLevMin -140 CellSelectionReselectionConf sNonIntraSearch 16 CellSelectionReselectionConf threshServingLow 0 LteNeighboringCellRelation threshXLow 0 CellSelectionReselectionConf qHyst dB2 CellReselectionConfLte tReselectionEUTRAN 2

LteSpeedDependentConf tReselectionEutraSfMedium oDot5

LteSpeedDependentConf tReselectionEutraSfHigh oDot25

SpeedStateEvalConf nCellChangeHigh 12

SpeedStateEvalConf nCellChangeMedium 4

SpeedStateEvalConf qHystSfHigh dB-6

SpeedStateEvalConf qHystSfMedium dB-6

Table 6-9: Parameters impacting measurements for inter-frequency (idle mode)

ReportConfigEUTRA thresholdEutraRsrp -120 ReportConfigEUTRA Threshold2EutraRsrp -100 ReportConfigEUTRA Hysteresis 2 ReportConfigEUTRA timeToTrigger ms100 RrcMeasurementConf filterCoefficientRSRP Fc8 LteNeighboringFreqConf offSetFreq dB0 ReportConfigEUTRA reportInterval ms240

ReportConfigEUTRA maxReportCells Check Recommendation

ReportConfigEUTRA reportAmount r8

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6.6.2 LTE – UMTS MOBILITY

Coexistence of various technologies requires the possibility of performing mobility between various types of RAN. Indeed, such mobility requires multi-standard UEs.

Parameters impacting LTE – UMTS mobility are presented in the table below.

CellReselectionConfUtraTdd qRxLevMin -115

CellSelectionReselectionConf sNonIntraSearch 16

CellSelectionReselectionConf threshServingLow 16

CellReselectionConfUtraTdd threshXLow 0

UtraNeighboring tReselectionUtra 2

UtraSpeedDependentConf tReselectionUtraSfMedium oDot5

UtraSpeedDependentConf tReselectionUtraSfHigh oDot25

SpeedStateEvalConf qHystSfHigh dB-6

SpeedStateEvalConf qHystSfMedium dB-6

Table 6-11: Parameters impacting LTE – UMTS Inter-Frequency (Idle Mode)

ReportConfigUTRA thresholdEutraRsrpB2 -100 ReportConfigUTRA thresholdUtraRscp -114 RrcMeasurementConf filterCoefficientOfQuantityConfigUtra fc4 ReportConfigUTRA hysteresis 4 ReportConfigUTRA timeToTrigger ms100 ReportConfigUTRA reportInterval ms240 ReportConfigUTRA maxReportCells 1 ReportConfigUTRA reportAmount r8

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MeasObjectUTRA offsetFreqUTRA 0

Table 6-12: Parameters impacting LTE – UMTS Inter-Frequency (Active Mode)

6.6.3 LTE – GSM MOBILITY

Parameters impacting LTE – GSM mobility are presented in the table below.

CellReselectionConfGERAN qRxLevMin -101

CellSelectionReselectionConf sNonIntraSearch 16

CellSelectionReselectionConf threshServingLow 16

CellReselectionConfGERAN threshXLow 0

GeranNeighboring tReselectionGERAN 2

GeranSpeedDependentConf tReselectionGERANSfMedium oDot5

GeranSpeedDependentConf tReselectionGERANSfHigh oDot25

SpeedStateEvalConf qHystSfHigh dB-6

SpeedStateEvalConf qHystSfMedium dB-6

Table 6-13: Parameters impacting LTE – GSM (Idle Mode)

ReportConfigGERAN thresholdEutraRsrpB2 -100

ReportConfigGERAN thresholdGeran -110

RrcMeasurementConf filterCoefficientOfQuantityConfigGERAN fc2

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ReportConfigGERAN timeToTrigger ms100

ReportConfigGERAN reportInterval ms240

ReportConfigGERAN maxReportCells 1

ReportConfigGERAN reportAmount r8

MeasObjectGERAN offsetFreqGERAN 0

Table 6-14: Parameters impacting LTE – GSM (Active Mode)

7 NEW FEATURES IN TLA6.0

In the table below is presented all the new features belonging to TLA6.0 and it is identified all the domains impacted by each feature.

For more information regarding the features the following link should be checked: TLA6.x FTS

Documents for Review.

Feature name Optimiz_ation Capacity Throughput Coverage Latenc_y Mobilit_y Attac_h MO_S

DL dual-layer BF for 8 antenna (commercial) Optim x x x x Rel9 DL MU-MIMO BF (TM8 Rank1) Optim x bCEM P1.1 for 8A configurations Optim x x x x x x BBU Configurations

for T/LA6.0 HW/Optim x x x x x x

BBU configuration clarification for one logic cell (churn 166011)

HW/Opt

im x x x x x x

support of multi-RRH per cell (one logic cell) for indoor coverage E2E/Opt im x x x x x Band 38 (2.6GHz) LTE eNodeB Configurations in TLA6.0 E2E x x x x x x Band 40 (2.3GHz) LTE eNodeB Configurations in TLA6.0 E2E x x x x x x

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Feature name Optimiz_ation Capacity Throughput Coverage Latenc_y Mobilit_y Attac_h MO_S

3GPP 36.104/141 Conformance test in TDD RF/Evol x x x x x TLA6.0 Release Upgrade Support KPI/OM C support ZUC only (w/o SNOW3G) for 8A field trial E2E TLA6.0 SW capacity target E2E/Opt im x x ATCR TD-RRH8x10-26 (8x10W RRH) RF/Optim x x x x TLA6.0 8A L1 counter introduction KPI/Opti m

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8 COVERAGE OPTIMIZATION HINTS

In this chapter it will be highlighted the main focus of testing and the primary steps that will allow to optimize a specific domain and the most important /priority parameters; in this case the domain addressed is coverage in LTE.

In this chapter it will be beaked in two sub-domains; Downlink Coverage and Uplink Coverage. Normally some questions arise, such as:

When to perform coverage optimization?

Which parameters can help extending /reducing the coverage?

Mainly the Coverage optimization can occur when the Link Budget is below expectations (Theoretical calculation).

Before starting playing with the parameterization; usually is part of best practice rules for in Near Cell /Mid Cell & Cell Edge test to follow up simple steps as:

Check the CQI

Evaluate RSSI vs. SNR relation Evaluate RSRP vs. RSRQ

Throughput Values for specific location

If we could guarantee that these values are “normal”, the chances to have performance issues are much less difficult to occur.

If regardless of the correct values, still facing some performance issues, the below parameters can be used in order to correct the situation.

When changing parameters; you can adopt a more error-free approach, meaning that a parameter is changed at each time. If three or four parameters are changed same time… it could be difficult to understand which one is bringing the improvement in performance.

As note; please remember that this can be a static test in each position, or can be a moving test… the same principles can be applied in both situations.

8.1 PARAMETERS OPTIMIZATION FOR IMPROVING DOWNLINK

COVERAGE

8.1.1 REFERENCESIGNALPOWER

The Reference Signal Power is a key RF parameter that impacts coverage.

Parameter referenceSignalPower configures the DL RS absolute power applied per Resource Element (REG) and per transmit antenna. This level is used as a power level reference (the power levels for all the other DL signals and channels are set relative to it).

ATTENTION! When modifying this parameter, all other signal power setting will be adjusted in accordance to a re-calculated power offset relative to the referenceSignalPower.

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LTE/IRC/APP/032749 V06.03 / EN Approved Standard 28/Oct/2013 Page 32/290 This parameter is expressed in dBm. It is converted into linear scale (miliwatts) according to the following formula:

Expected behaviour when changing this parameter:

The higher the setting, the larger the cell coverage on the downlink, but leaves smaller power headroom available for other downlink signals and channels.

The lower the value, the smaller the cell coverage on the downlink axis, but larger power headroom is available for other downlink signals and channels.

Note: The following Table 8-1 translates the expected behaviour in terms of cellDLTotalPower when changing the reference Signal Power; some difference may occur if other sets of parameters are used also.

TLA6.0 supports 8 antennas and 2 antennas with OLC eNB (One Logical Cell, also named Supper Cell), 2 Antennas OLC eNB supports transmission mode 1/2/3/4 and 8 Antennas eNB supports transmission mode 1/2/3/7/8.

For RSRP, RSSI, RSRQ relationship, please refer to 3GPP TS36.214.

Antennas transmissionMode cellDLTotalPower (dBm) Bandwidth referenceSignalPower (dBm) 2 antennas (2×20w RRH) TM1, TM2, TM3, TM4 43 n50-10MHz 18 n100-20MHz 15 8 antennas (8×5w RRH) TM1, TM2, TM3, TM7, TM8 37 n50-10MHz _{n100-20MHz 13}16 8 antennas (8×10w RRH) TM1, TM2, TM3, TM7, TM8 40 n50-10MHz 16 (per of 2 carriers) or 19 (single carrier) n100-20MHz 13 (per of 2 carriers) or 16 (single carrier) Table 8-1: In the trial mode, the default setting for parameter referenceSignalPower Note that, since TLA6.0 MIM15.1.3 template v12, the CRS power boosting by increasing

referenceSignalPower and decreasing paOffset are recommended (for detail info please refer to section 8.2.5).

The recent change in terms of recommendation for the CRS booting is due to live testing at JQHQ OTA field test results, SINR increasing were seen after tuning power setting from the non-CRS power boosting values.

The testing procedure should comprise the following steps:

Step 1: Set the referenceSignalPower and other DL signal/channels power setting as default sets of values without RS boosting.

Step 2: Connect the UE in Near-Cell radio conditions with DL full buffer FTP transfer and perform driver test towards Celledge till UE drop. For a more consistent data we recommend a drive back as well logged in another trace.

Step 3: Using the same cell and same route, choose referenceSignalPower and other DL signal/channels as the sets of values with RS boosting and repeat Step2.

Step 4: Post process the logged data and provide results in terms of RSRP, SINR and coverage statistic.

P [mW] = 100.1×referenceSignalPower

(33)

LTE/IRC/APP/032749 V06.03 / EN Approved Standard 28/Oct/2013 Page 33/290 Figure 8.1-1: CRS boosting Vs. non-boosting test route (Field Results JQHQ OTA–SubUrban)

Figure 8.1-2: SINR with CRS boosting Vs. without CRS boosting (Field Results JQHQ OTA– SubUrban)

Based on the test results, we can conclude that, SINR with RS boosting is about 2~5dB higher than that without RS boosting. This will make benefit for downlink channel quality estimation and improve DL coverage, although based on JQHQ OTA field test, basically no gain on throughput could be seen after CRS power boosting, further field tests will be done in CMCC commercial deployment.

8.1.2 PHICHRESOURCE

PHICH channels are grouped in PHICH groups. Each PHICH group consists of 8 PHICH channels (hence conveys 8 ACK/NACKs) that use the same resources, PHICH channels of a same group being separated by orthogonal sequences. The number of PHICH groups in TDD subframe i is:

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 -123 -120 -117 -114 -111 -108 -105 -102 -99 -96 -93 -90 -87 -84 -81 -78 -75 -72 -69 -66 SI NR RSRP

JQHQ OTA RSRP Vs. SINR

Avg. SINR without CRS boosting

Avg. SINR with CRS boosting

(34)

LTE/IRC/APP/032749 V06.03 / EN Approved Standard 28/Oct/2013 Page 34/290 Where:

Ng ∈{1/6 ,1/2 , 1, 2} and is configured by parameter phichResource NDL

RB is the total number of RBs in the downlink and is configured by parameter

FrequencyAndBandwidthTDD :: Bandwidth

In TDD, the number of PHICH groups may vary between downlink subframes and is given by

group PHICH

N

m

_i



, where m is given below: i

Uplink-downlink configuration Subframe number 0 1 2 3 4 5 6 7 8 9 0 2 1 - - - 2 1 - - - 1 0 1 - - 1 0 1 - - 1 2 0 0 - 1 0 0 0 - 1 0 3 1 0 - - - 0 0 0 1 1 4 0 0 - - 0 0 0 0 1 1 5 0 0 - 0 0 0 0 0 1 0 6 1 1 - - - 1 1 - - 1 Table 8-2: The factor m for TDD _i

A PHICH group consists of 3 REGs over either 1 or 3 OFDM symbols, depending on the value of parameter phich-Duration (“normal” or “extended”). This parameter can only be set to “extended” if the CFI is equal to 3.

Expected behaviour when changing this parameter:

Setting the value low will result in lower number of PHICH groups in a subframe, so the higher the number of ACK/NACKs that need to be sent out the longer the buffer, eventually leading to failing to transmit the messages.

Setting value high will impact in having a higher number of PHICH groups in a subframe, so the fewer ACK/NACKs needed to be transmitted, OFDM symbols are not used and the allocated resources for this process go to waste.

Note that, currently, ALU LTE eNB only support Ng=1, i.e. parameter phichResource=1.

8.1.3 N310 AND T310

n310 defines the maximum number of consecutive "out-of-sync" indications received from lower layers for the UE to detect physical layer problems. It is broadcasted in SIB2.

t310 specifies the start value for the UE timer T310. This timer is started in the UE in RRC connected mode upon detecting radio link problems. At timer expiry the UE will go to RRC idle mode if security is not activated, else initiate the RRC connection re-establishment procedure. It is broadcasted in SIB2.

i

Recommended Value & Only Supported Value= "1"

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      prefix cyclic extended for 8 prefix cyclic normal for 8 DL RB g DL RB g group PHI CH N N 2 N N N

LTE Optimization Handbook