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RAN 6.1
Network Optimization Parameter Reference
Issue
01
Date
2007-08-30
Part Number
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RAN Network Optimization Parameter Reference
Contents
Contents About This Document.....................................................................................................................1 1 Power Control Parameters........................................................................................................1-1 1.1 Uplink Power Control Parameters...................................................................................................................1-2 1.1.1 Power Offset Between Access Preamble and Message Control Part.....................................................1-4 1.1.2 PRACH Initial Transmit Power Constant..............................................................................................1-5 1.1.3 PRACH Power Ramp Step.....................................................................................................................1-6 1.1.4 Maximum Preamble Retransmit Attempts.............................................................................................1-6 1.1.5 Maximum Preamble Loop......................................................................................................................1-7 1.1.6 Default DPCCH Transmit Power Constant............................................................................................1-8 1.1.7 Maximum Allowed Uplink Transmit Power of the UE.........................................................................1-8 1.1.8 RRC/HHO Process SRB Delay............................................................................................................1-10 1.1.9 RRC/HHO Process DPCCH Power Control Preamble Length............................................................1-11 1.2 Downlink Power Control Parameters............................................................................................................1-11 1.2.1 Maximum Downlink Transmit Power of the Radio Link....................................................................1-13 1.2.2 Minimum Downlink Transmit Power of the Radio Link.....................................................................1-14 1.2.3 Cell PCPICH Transmit Power..............................................................................................................1-15 1.2.4 Maximum PCPICH Transmit Power....................................................................................................1-16 1.2.5 Minimum PCPICH Transmit Power....................................................................................................1-16
2 Handover Parameters................................................................................................................2-1 2.1 Intra-Frequency Handover Parameters............................................................................................................2-2 2.1.1 Softer Handover Combination Indication Switch..................................................................................2-4 2.1.2 Intra-Frequency Measurement L3 Filter Coefficient.............................................................................2-4 2.1.3 Weighting Factor....................................................................................................................................2-6 2.1.4 Soft Handover Relative Thresholds.......................................................................................................2-7 2.1.5 Event 1F Absolute Thresholds...............................................................................................................2-8 2.1.6 Hysteresis Related to Soft Handover.....................................................................................................2-9 2.1.7 Time to Trigger Related to Soft Handover...........................................................................................2-11 2.1.8 Minimum Quality Threshold of Soft Handover...................................................................................2-13 2.1.9 Affect 1A and 1B Event Thresholds Flag............................................................................................2-14 2.1.10 Cell Individual Offset.........................................................................................................................2-14 2.2 Inter-Frequency Handover Parameters..........................................................................................................2-15 2.2.1 Inter-Frequency Measurement Report Mode.......................................................................................2-19 Issue 01 (2007-08-30)
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2.2.2 Inter-Frequency Measurement Item.....................................................................................................2-20 2.2.3 Inter-Frequency Measurement Layer 3 Filter Coefficients..................................................................2-22 2.2.4 Frequency Weighting Factor................................................................................................................2-23 2.2.5 Hysteresis Related to Inter-Frequency Handover................................................................................2-24 2.2.6 Time to Trigger Related to Inter-Frequency Hard Handover...............................................................2-25 2.2.7 RSCP-Based Inter-Frequency Measurement Start/Stop Thresholds....................................................2-26 2.2.8 EC/No-based Inter-Frequency Measurement Start/Stop Thresholds...................................................2-27 2.2.9 Target Frequency Trigger Threshold of Inter-Frequency Coverage....................................................2-28 2.2.10 Current Used Frequency Quality Threshold of Inter-Frequency Handover.......................................2-29 2.2.11 Inter-Frequency Measurement Minimum Access Thresholds...........................................................2-30 2.2.12 Cell Individual Offset.........................................................................................................................2-31 2.2.13 Inter-Frequency/Inter-RAT Algorithm Switches...............................................................................2-32 2.2.14 Inter-Frequency/Inter-RAT Measurement Threshold Choice............................................................2-33 2.2.15 Inter-Frequency Measure Timer Length............................................................................................2-34 2.3 Coverage-Based Inter-RAT Handover Management Parameters.................................................................2-34 2.3.1 Inter-RAT Measurement L3 Filter Coefficients...................................................................................2-39 2.3.2 Inter-RAT Measurement Report Mode................................................................................................2-39 2.3.3 Frequency Weighting Factor................................................................................................................2-41 2.3.4 Inter-RAT Period Report Interval........................................................................................................2-42 2.3.5 BSIC Verify Selection Switch..............................................................................................................2-42 2.3.6 Inter-RAT Measurement Quantity.......................................................................................................2-43 2.3.7 RSCP-Based Inter-RAT Measurement Start/Stop Thresholds.............................................................2-44 2.3.8 Ec/No-Based Inter-RAT Measurement Start/Stop Thresholds............................................................2-45 2.3.9 Inter-RAT Handover Judging Thresholds............................................................................................2-46 2.3.10 Time to Trigger Related to Inter-RAT Handover..............................................................................2-47 2.3.11 Hysteresis Related to Coverage-Based Inter-RAT Handover............................................................2-48 2.3.12 Time to Trigger for Verified GSM Cell.............................................................................................2-49 2.3.13 Time to Trigger for Non-verified GSM Cell......................................................................................2-50 2.3.14 Penalty Time for Inter-RAT Handover..............................................................................................2-51 2.3.15 Cell Individual Offset.........................................................................................................................2-51 2.3.16 Current Used Frequency Quality Threshold of Inter-RAT Handover...............................................2-52 2.3.17 Inter-RAT Measure Timer Length.....................................................................................................2-53 2.4 Non Coverage-Based Inter-RAT Handover Management Parameters.........................................................2-54 2.4.1 Inter-RAT Service Handover Switches................................................................................................2-56 2.4.2 Inter-RAT Measurement L3 Filter Coefficient....................................................................................2-57 2.4.3 Hysteresis of Event 3C.........................................................................................................................2-57 2.4.4 Time to Trigger for Event 3C...............................................................................................................2-59 2.4.5 BSIC Verify Selection Switch..............................................................................................................2-59 2.4.6 Non Coverage-Based Inter-RAT Handover Judging Thresholds.........................................................2-60 2.4.7 Penalty Time for Inter-RAT Handover................................................................................................2-61 2.4.8 Inter-RAT Handover Max Attempt Times...........................................................................................2-62 2.4.9 Inter-RAT Measure Timer Length.......................................................................................................2-62 ii
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2.5 Blind Handover Management Parameters.....................................................................................................2-63 2.5.1 Blind Handover Flag............................................................................................................................2-64 2.5.2 Blind Handover Priority.......................................................................................................................2-65 2.6 Cell Selection and Reselection......................................................................................................................2-66 2.6.1 Measurement Hysteresis Parameters....................................................................................................2-69 2.6.2 Load Level Offsets...............................................................................................................................2-70 2.6.3 Minimum Quality Criterion.................................................................................................................2-71 2.6.4 Minimum Access Level.......................................................................................................................2-72 2.6.5 Cell Reselection Start Thresholds........................................................................................................2-72 2.6.6 Reselection Hysteresis Time................................................................................................................2-73 2.6.7 Minimum Access Level for Inter-RAT Cell........................................................................................2-74 2.6.8 2G Idle Mode MS's Searching for 3G Cell Signal Level Threshold....................................................2-75 2.6.9 3G Cell Reselection Signal Level Offset.............................................................................................2-76 2.6.10 3G Cell Reselection Signal Level Threshold.....................................................................................2-77 2.7 Neighbor Management Parameters...............................................................................................................2-77 2.7.1 Neighbor Priority Flag.........................................................................................................................2-78 2.7.2 Neighbor Priority..................................................................................................................................2-78
3 Admission Control Parameters................................................................................................3-1 3.1 Uplink and Downlink Initial Access Rates of BE Service..............................................................................3-5 3.2 Intelligent Admission Algorithm Switch........................................................................................................3-5 3.3 Uplink Total Equivalent User Number...........................................................................................................3-7 3.4 Downlink Total NonHSDPA Equivalent User Number.................................................................................3-8 3.5 AMR Voice Uplink Threshold for Conversation Service...............................................................................3-8 3.6 Non AMR Voice Uplink Threshold of Conversation Service........................................................................3-9 3.7 AMR Voice Downlink Threshold for Conversation Service........................................................................3-10 3.8 Non AMR Voice Downlink Threshold of Conversation Service.................................................................3-11 3.9 Uplink Threshold for Other Services............................................................................................................3-12 3.10 Downlink Threshold for Other Services.....................................................................................................3-13 3.11 Uplink Handover Admission Threshold.....................................................................................................3-14 3.12 Downlink Handover Admission Threshold.................................................................................................3-15 3.13 Downlink Total Power Threshold...............................................................................................................3-16 3.14 Uplink Handover Credit Reserved SF.........................................................................................................3-17 3.15 Downlink Handover Credit and Channel Code Resource Reserved SF.....................................................3-17 3.16 Resources Reserved for Common Channel Load.......................................................................................3-18
4 Load Control Parameters..........................................................................................................4-1 4.1 Cell Load Reshuffling Algorithm Parameters.................................................................................................4-2 4.1.1 Uplink and Downlink LDR Algorithm Switches...................................................................................4-6 4.1.2 LDR Period Timer Length.....................................................................................................................4-7 4.1.3 Uplink and Downlink LDR Trigger Thresholds and Release Thresholds.............................................4-8 4.1.4 Uplink or Downlink LDR Actions.........................................................................................................4-9 4.1.5 Uplink/Downlink LDR Action Handing User Number.......................................................................4-10 4.1.6 Uplink and Downlink Inter-Frequency Cell Load Handover Load Space Thresholds........................4-13 Issue 01 (2007-08-30)
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4.1.7 Uplink and Downlink Inter-Frequency Cell Load Handover Maximum Band Width.........................4-13 4.1.8 Cell SF Reserved Threshold.................................................................................................................4-14 4.1.9 Uplink or Downlink Credit SF Reserved Threshods...........................................................................4-15 4.1.10 LDR Code Priority Indicator..............................................................................................................4-16 4.1.11 MBMS Power Control Service Priority Threshold............................................................................4-16 4.2 Cell Overload Congestion Control Algorithm Parameters...........................................................................4-17 4.2.1 Uplink and Downlink OLC Algorithm Switches.................................................................................4-19 4.2.2 OLC Period Timer Length...................................................................................................................4-20 4.2.3 Uplink and Downlink OLC Trigger Threshold and Release Threshold..............................................4-21 4.2.4 Uplink and Downlink OLC Fast TF Restriction Times.......................................................................4-22 4.2.5 Uplink and Downlink OLC Fast TF Restrict RAB Number................................................................4-22 4.2.6 OLC Fast TF Restrict Data Rate Restrict Timer Length And Recover Timer Length........................4-23 4.2.7 OLC Fast TF Restrict Data Rate Restrict Coefficient..........................................................................4-24 4.2.8 Uplink and Downlink Release RAB Number......................................................................................4-24
5 PS Service Rate Control Parameters.......................................................................................5-1 5.1 BE Service Related Threshold Parameters......................................................................................................5-2 5.1.1 BE Service Handover Rate Threshold................................................................................................... 5-3 5.1.2 Uplink/Downlink BE Service Insured Rate...........................................................................................5-4 5.1.3 UpLink and Downlink BE traffic DCH decision threshold...................................................................5-5 5.1.4 DL Streaming Threshold on HSDPA.....................................................................................................5-6 5.1.5 DL BE Traffic Threshold on HSDPA....................................................................................................5-6 5.1.6 UL BE Traffic Threshold on HSUPA....................................................................................................5-7 5.1.7 UL Streaming Traffic Threshold on HSUPA.........................................................................................5-7 5.1.8 Streaming Service HSUPA Transmission Mode................................................................................... 5-8 5.2 Dynamic Channel Configuration Control Parameters.................................................................................... 5-8 5.2.1 Traffic Upper Threshold.......................................................................................................................5-10 5.2.2 Traffic Lower Threshold......................................................................................................................5-11 5.2.3 Time to Trigger Event 4A....................................................................................................................5-12 5.2.4 Time to Trigger Event 4B....................................................................................................................5-12 5.2.5 Pending Time after Trigger Event 4A..................................................................................................5-13 5.2.6 Pending time after trigger Event 4B.....................................................................................................5-14 5.2.7 Uplink and Downlink DCCC Rate Thresholds....................................................................................5-15 5.2.8 Uplink and Downlink Middle Rate Thresholds...................................................................................5-15 5.2.9 Uplink and Downlink Rate Adjust Levels...........................................................................................5-16 5.2.10 Low activity bitrate threshold............................................................................................................5-17 5.3 Link Stability Parameters..............................................................................................................................5-17 5.3.1 Event Ea Relative Threshold................................................................................................................5-18 5.3.2 Event Eb Relative Threshold................................................................................................................5-19 5.3.3 Uplink Full Coverage Rate...................................................................................................................5-19 5.3.4 Downlink Full Coverage Rate..............................................................................................................5-20 5.4 State Transfer Parameters..............................................................................................................................5-21 5.4.1 DCH to FACH State Transition Timer................................................................................................5-22 iv
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5.4.2 DCH to FACH / FACH to PCH State Transition Traffic 4B Threshold..............................................5-23 5.4.3 FACH to PCH State Transition Timer.................................................................................................5-23 5.4.4 Cell ReSelection Timer........................................................................................................................5-24 5.4.5 FACH to DCH Traffic Report Threshold............................................................................................5-25 5.4.6 FACH to DCH Traffic Time to trigger................................................................................................5-25 5.5 PS Inactive.....................................................................................................................................................5-26 5.5.1 Interactive Service T1..........................................................................................................................5-27 5.5.2 Interactive Service T2..........................................................................................................................5-28 5.5.3 Background Service T1........................................................................................................................5-28 5.5.4 Background Service T1........................................................................................................................5-29 5.5.5 IMS Service T1....................................................................................................................................5-30 5.5.6 IMS Service T2....................................................................................................................................5-30 5.6 RLC Retransmission Monitor Algorithm Parameters...................................................................................5-31 5.6.1 Time to Start Re-TX Monitor...............................................................................................................5-32 5.6.2 Re-Tx Monitor Period..........................................................................................................................5-33 5.6.3 Retransmission Filter Coefficient.........................................................................................................5-34 5.6.4 Event A threshold.................................................................................................................................5-34 5.6.5 Event A Time to Trigger......................................................................................................................5-35 5.6.6 Event A Pending Time after Trigger....................................................................................................5-35 5.6.7 Event A Report Period.........................................................................................................................5-36 5.6.8 Event B Threshold................................................................................................................................5-36 5.6.9 Event B Time to Trigger......................................................................................................................5-37 5.6.10 Event B Pending Time after Trigger..................................................................................................5-38
6 Miscellaneous Topic Parameters.............................................................................................6-1 6.1 Cell Channel Power Distribution Parameters..................................................................................................6-2 6.1.1 Maximum Cell Transmit Power.............................................................................................................6-3 6.1.2 Cell PCPICH Transmit Power................................................................................................................6-4 6.1.3 PSCH and SSCH Transmit Power.........................................................................................................6-4 6.1.4 BCH Transmit Power.............................................................................................................................6-5 6.1.5 Maximum FACH Transmit Power.........................................................................................................6-6 6.1.6 PCH Transmit Power.............................................................................................................................6-7 6.1.7 PICH Transmit Power............................................................................................................................6-7 6.1.8 AICH Transmit Power...........................................................................................................................6-8 6.2 Paging Parameters...........................................................................................................................................6-9 6.2.1 Paging Cycle Coefficient.......................................................................................................................6-9 6.2.2 Number of Paging Retransmit..............................................................................................................6-10 6.3 RRC Connection Setup Parameters...............................................................................................................6-11 6.3.1 T300 and N300.....................................................................................................................................6-11 6.4 Synchronization Parameters..........................................................................................................................6-12 6.4.1 Number of Successive In-sync Indications..........................................................................................6-14 6.4.2 Number of Successive Out-of-sync Indications...................................................................................6-14 6.4.3 Radio Link Failure Timer Duration.....................................................................................................6-15 Issue 01 (2007-08-30)
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6.4.4 N312 and T312.....................................................................................................................................6-16 6.4.5 N313, N315, and T313.........................................................................................................................6-17 6.5 Location Update Parameters.........................................................................................................................6-17 6.5.1 Periodic Location Update Timer..........................................................................................................6-18 6.6 User Priority Related Parameters..................................................................................................................6-18 6.6.1 User Priority of Allocation/Retension Priority 1~14...........................................................................6-19 6.6.2 Integrate Priority Configured Reference..............................................................................................6-20 6.6.3 Indicator of Carrier Type Priority........................................................................................................6-21
7 HSDPA Parameters....................................................................................................................7-1 7.1 HSDPA Power Resource Management Parameters........................................................................................7-2 7.1.1 HS-DPCCH Power Management Parameters........................................................................................7-2 7.1.2 Total Power of HSDPA and Measurement Power Offset Constant.....................................................7-10 7.2 HSDPA Code Resource Management Algorithm Parameters......................................................................7-12 7.2.1 HSDPA Code Resource Distribution Mode.........................................................................................7-13 7.2.2 Number of HS-PDSCH Codes.............................................................................................................7-13 7.2.3 Number of Maximum HS-PDSCH Codes...........................................................................................7-14 7.2.4 Number of Minimum HS-PDSCH Codes............................................................................................7-14 7.2.5 Number of HS-SCCH Codes................................................................................................................7-15 7.3 HSDPA Mobility Management Parameters..................................................................................................7-16 7.3.1 HSPA Handover Protection Length.....................................................................................................7-16 7.4 HSDPA Direct Retry and Switch of Channel Types Parameters..................................................................7-18 7.4.1 D2H Retry Timer Length.....................................................................................................................7-19 7.4.2 Timer Length of D2H Intra-Handover.................................................................................................7-19 7.4.3 Timer Length of D2H Inter-Handover.................................................................................................7-20 7.4.4 Timer Length of Multi-Carrier Handover............................................................................................7-21 7.4.5 Compress Mode Permission Indication on HSDPA............................................................................7-21 7.5 HSDPA Admission Control Algorithm.........................................................................................................7-22 7.5.1 Maximum HSDPA Users of NodeB....................................................................................................7-23 7.5.2 UL HS-DPCCH Reserve Factor...........................................................................................................7-24 7.5.3 HSDPA Streaming PBR Threshold......................................................................................................7-24 7.5.4 HSDPA Best Effort PBR Threshold....................................................................................................7-25 7.5.5 Maximum HSDPA User Number........................................................................................................7-25
8 HSUPA Parameters....................................................................................................................8-1 8.1 HSUPA MAC-e Scheduling Algorithm Parameters.......................................................................................8-2 8.1.1 Maximum Target Uplink Load Factor...................................................................................................8-2 8.1.2 Target Non-Serving E-DCH to Total E-DCH Power Ratio...................................................................8-3 8.2 HSUPA Admission Control Algorithm...........................................................................................................8-4 8.2.1 Maximum HSUPA User Number.......................................................................................................... 8-4 8.2.2 DL HSUPA Reserved Factor ................................................................................................................ 8-5 8.2.3 NodeB Maximum HSUPA User Number..............................................................................................8-6
9 MBMS Parameters.....................................................................................................................9-1 vi
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9.1 MBMS Admission and Load Control Parameters...........................................................................................9-2 9.1.1 Maximum Transmit Power of the FACH...............................................................................................9-3 9.1.2 Minimum Coverage Percentage of the MBMS Service with the Highest Priority................................9-4 9.1.3 Minimum Coverage Percentage of the MBMS Service with the Lowest Priority.................................9-5 9.1.4 Service Priority Threshold for Decreasing Power..................................................................................9-5 9.1.5 MBMS Preempt Algorithm Switch........................................................................................................9-6 9.2 FLC/FLD Algorithm Parameters....................................................................................................................9-7 9.2.1 FLC Algorithm Switch...........................................................................................................................9-7
10 Algorithm Switches...............................................................................................................10-1 10.1 Connection-Oriented Algorithm Switches in RNC.....................................................................................10-2 10.1.1 Channel Algorithm Switches.............................................................................................................10-2 10.1.2 Handover Algorithm Switches...........................................................................................................10-6 10.1.3 Power Control Algorithm Switches.................................................................................................10-11 10.1.4 HSPA Algorithm Switches...............................................................................................................10-13 10.1.5 DRD Algorithm Switches................................................................................................................10-15 10.2 Cell Algorithm Switches...........................................................................................................................10-16 10.2.1 Cell Algorithm Switches..................................................................................................................10-16 10.2.2 Uplink Admission Control Algorithm Switch ................................................................................10-18 10.2.3 Downlink Admission Control Algorithm Switch.............................................................................10-19 10.3 Other Algorithm Switches.........................................................................................................................10-20 10.3.1 Iub CAC Algorithm Switches..........................................................................................................10-20 10.3.2 Iub Bandwidth Congestion Control Algorithm Switch....................................................................10-20 10.3.3 Intra-Frequency Measurement Control Information Indication.......................................................10-21 10.3.4 Inter-Frequency/Inter-RAT Measurement Indication......................................................................10-22 10.3.5 FACH Measurement Indicator ........................................................................................................10-22
11 Transmission Resource Management Parameters...........................................................11-1 11.1 Transmission Common Parameters.............................................................................................................11-2 11.1.1 AAL2 Path Type................................................................................................................................11-2 11.1.2 IP Path Type.......................................................................................................................................11-3 11.1.3 Per-Hop Behavior...............................................................................................................................11-3 11.2 Iub Admission Control Parameters.............................................................................................................11-4 11.2.1 Reserved Bandwidth for Forward/Backward Handover....................................................................11-4 11.3 Iub Congestion Control Parameters............................................................................................................11-5 11.3.1 Forward/Backward Congestion Threshold.........................................................................................11-8 11.3.2 Forward/Backward Congestion Clear Threshold...............................................................................11-9 11.3.3 Iub Bandwidth Congestion Control Algorithm Switch......................................................................11-9 11.3.4 Timer Length for Iub Bandwidth Restriction Service Rate Reduction............................................11-10 11.3.5 Iub Congestion Factors.....................................................................................................................11-11
12 Parameters Configured on NodeB LMT............................................................................12-1 12.1 HSDPA Flow Control Parameters...............................................................................................................12-2 12.1.1 HSDPA Bandwidth Adjustment Switch............................................................................................12-2 Issue 01 (2007-08-30)
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12.1.2 Frame Discard Rate Threshold on Iub Interface................................................................................12-3 12.1.3 Time Delay Threshold on Iub Interface.............................................................................................12-4 12.2 HSDPA MAC-hs Scheduling Algorithm Parameters.................................................................................12-5 12.2.1 Resource Allocate Method.................................................................................................................12-8 12.2.2 Scheduling Method............................................................................................................................12-9 12.2.3 Maximum Retransmission Count.....................................................................................................12-10 12.2.4 Power Margin...................................................................................................................................12-10 12.2.5 HS-SCCH Power Control Method...................................................................................................12-11 12.2.6 HS-SCCH Fixed Power or Initial Transmit Power..........................................................................12-12 12.2.7 Target HS-SCCH FER.....................................................................................................................12-12 12.2.8 Initial BLER of Data Transfer .........................................................................................................12-13 12.2.9 Resource Limiting Switch................................................................................................................12-14 12.2.10 HSDPA Dynamic Code Switch......................................................................................................12-14 12.2.11 16QAM Switch..............................................................................................................................12-15 12.2.12 CQI Filter Alpha.............................................................................................................................12-16 12.2.13 GBR for SPI...................................................................................................................................12-16 12.2.14 Weight for SPI................................................................................................................................12-18 12.2.15 Resource Limiting Ratio for SPI....................................................................................................12-18 12.3 HSUPA MAC-e Scheduling Algorithm Parameters.................................................................................12-19 12.3.1 AG Threshold...................................................................................................................................12-20 12.3.2 Average Rate Initial Value...............................................................................................................12-20 12.3.3 GBR Schedule Switch......................................................................................................................12-21 12.3.4 Sort Rate Weight..............................................................................................................................12-22 12.3.5 Sort Rate RSN Weight.....................................................................................................................12-22 12.4 HSUPA Power Control Parameters...........................................................................................................12-23 12.4.1 Power Control Algorithm Switches for Downlink Control Channel...............................................12-23 12.4.2 Fixed Power Control Mode Algorithm Parameters..........................................................................12-28 12.4.3 Dynamic Power Control Mode Algorithm Parameters....................................................................12-32 12.5 Local Cell Management Parameters..........................................................................................................12-36 12.5.1 Cell Radius.......................................................................................................................................12-36 12.5.2 Cell Handover Radius......................................................................................................................12-37
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Figures
Figures Figure 7-1 Impact from over long HSPA protection length...............................................................................7-17
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Tables
Tables Table 1-1 List of uplink power control parameters..............................................................................................1-2 Table 1-2 List of downlink power control parameters.......................................................................................1-12 Table 1-3 Maximum and minimum downlink transmit powers.........................................................................1-13 Table 2-1 List of intra-frequency handover parameters.......................................................................................2-2 Table 2-2 List of inter-frequency handover parameters.....................................................................................2-15 Table 2-3 List of coverage-based inter-RAT handover management parameters..............................................2-35 Table 2-4 List of non-coverage-based inter-RAT handover management parameters.......................................2-55 Table 2-5 List of blind handover management parameters................................................................................2-63 Table 2-6 List of cell selection and reselection parameters................................................................................2-66 Table 2-7 List of neighbor management parameters..........................................................................................2-77 Table 3-1 List of admission control parameters...................................................................................................3-1 Table 4-1 List of cell load reshuffling (LDR) algorithm parameters................................................................... 4-2 Table 4-2 List of smart load control parameters.................................................................................................4-17 Table 5-1 List of BE service related threshold parameters...................................................................................5-2 Table 5-2 List of dynamic channel configuration parameters..............................................................................5-9 Table 5-3 List of link stability parameters..........................................................................................................5-17 Table 5-4 List of state transfer parameters.........................................................................................................5-21 Table 5-5 List of PS inactive parameters............................................................................................................5-26 Table 5-6 List of RLC retransmission monitor algorithm parameters...............................................................5-31 Table 6-1 List of cell channel power distribution parameters..............................................................................6-2 Table 6-2 List of paging parameters.....................................................................................................................6-9 Table 6-3 List of RRC connection setup parameters..........................................................................................6-11 Table 6-4 List of synchronization parameters....................................................................................................6-13 Table 6-5 List of location update parameters.....................................................................................................6-18 Table 6-6 List of user priority related parameters..............................................................................................6-19 Table 7-1 List of HS-DPCCH power control parameters.....................................................................................7-2 Table 7-2 List of total power of HSDPA and measurement power offset constant...........................................7-10 Table 7-3 List of HSDPA code resource management algorithm parameters....................................................7-12 Table 7-4 List of HSDPA mobility management parameters.............................................................................7-16 Table 7-5 List of HSDPA direct retry and switch of channel types parameters.................................................7-18 Table 7-6 List of HSDPA admission control algorithm parameters..................................................................7-22 Table 8-1 List of HSUPA MAC-e scheduling algorithm parameters.................................................................. 8-2 Table 8-2 List of HSUPA admission control algorithm parameters.................................................................... 8-4 Issue 01 (2007-08-30)
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Table 9-1 List of MBMS admission and preempt algorithm parameters.............................................................9-2 Table 9-2 List of FLC/FLD algorithm parameters...............................................................................................9-7 Table 10-1 List of channel algorithm switches..................................................................................................10-3 Table 10-2 List of handover algorithm switches................................................................................................10-6 Table 10-3 List of power control algorithm switches.......................................................................................10-12 Table 10-4 List of HSPA algorithm switches...................................................................................................10-13 Table 10-5 List of DRD algorithm switches....................................................................................................10-15 Table 10-6 List of cell algorithm switches.......................................................................................................10-16 Table 10-7 CAC algorithm switches................................................................................................................10-20 Table 11-1 List of transmission common parameters........................................................................................11-2 Table 11-2 List of Iub admission control parameters.........................................................................................11-4 Table 11-3 List of Iub congestion control parameters........................................................................................11-6 Table 11-4 Iub Congestion Factor Configuration.............................................................................................11-12 Table 12-1 List of HSDPA flow control parameters..........................................................................................12-2 Table 12-2 List of HSDPA MAC-hs scheduling algorithm parameters.............................................................12-5 Table 12-3 GBR, weight and resource limiting ratio for SPI...........................................................................12-17 Table 12-4 List of HSUPA MAC-e scheduling algorithm parameters............................................................12-19 Table 12-5 List of power control algorithm switches for downlink control channel.......................................12-23 Table 12-6 List of fixed power control mode algorithm parameters................................................................12-28 Table 12-7 List of dynamic power control mode algorithm parameters..........................................................12-32 Table 12-8 List of local cell management parameters......................................................................................12-36
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About This Document
About This Document
Purpose This document provides the engineering technician of commercial office with a parameter setting baseline and parameter adjustment instructions.
Related Versions The following table lists the product versions related to this document. Product Name
Version
RNC
V200R009
NodeB
V100R008
Intended Audience This document is intended for: l
RNP engineers
l
RNO engineers
Update History Refer to Changes in RAN Network Optimization Parameter Reference.
Organization 1 Power Control Parameters Power control is a key WCDMA technique, through which near and far effect, shadow fading and fast fading can be overcome to ensure uplink and downlink network performance, reduce network interference and improve the system quality and capacity. As a result, power control parameter values have great impact on the network. 2 Handover Parameters Handover aims to ensure communication continuity and good communication quality. Handovers in WCDMA system are of the following types: soft handover, softer handover, intrafrequency hard handover, inter-frequency hard handover, inter-RAT hard handover and so on. Handover emerges as the important factor affecting network performance, and handover Issue 01 (2007-08-30)
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optimization is also significant in network optimization. Handover parameters are described according to the handover classification. 3 Admission Control Parameters Admission control is a way for coordinating the WCDMA system capacity, coverage and quality, and it ensures the system stability and QoS requirement by control over user access. 4 Load Control Parameters Load control is another very important function in WCDMA system. It maintains the system load within the normal range to ensure that the system’s overall QoS is in the normal range. The load control includes LDR (Load Reshuffling) and OLC (Overload Control). 5 PS Service Rate Control Parameters The PS Service rate control includes dynamic channel configuration, state transfer. 6 Miscellaneous Topic Parameters Special topic parameters include parameters for cell channel power distribution, paging, RRC connection setup, synchronization and location updating. 7 HSDPA Parameters HSDPA parameters include HSDPA power resource management parameters, HSDPA code resource management algorithm parameters, HSDPA mobility management parameters, HSDPA direct retry and switch of channel types parameters, and HSDPA call admission control algorithm parameters. 8 HSUPA Parameters HSUPA parameters include HSUPA MAC-e scheduling algorithm parameters, HSUPA power control parameters, and HSUPA admission control parameters. 9 MBMS Parameters MBMS parameters mainly include MBMS admission and load control parameters. 10 Algorithm Switches In the RNC, algorithm switches are divided into two classes: connection-oriented algorithm switches and cell-oriented algorithm switches. 11 Transmission Resource Management Parameters The common configurable transmission parameters are listed here. 12 Parameters Configured on NodeB LMT The parameters configured on the NodeB LMT described here mainly consist of the HSDPA flow control parameters, the HSDPA MAC-hs scheduling algorithm parameters, the HSUPA MAC-e scheduling algorithm parameters, the HSUPA power control parameters and the local cell management parameters.
Conventions 1. Symbol Conventions The following symbols may be found in this document. They are defined as follows 2
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Indicates a hazard with a high level of risk that, if not avoided, will result in death or serious injury. Indicates a hazard with a medium or low level of risk which, if not avoided, could result in minor or moderate injury. Indicates a potentially hazardous situation that, if not avoided, could cause equipment damage, data loss, and performance degradation, or unexpected results. Indicates a tip that may help you solve a problem or save your time. Provides additional information to emphasize or supplement important points of the main text.
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Convention
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Power Control Parameters
About This Chapter Power control is a key WCDMA technique, through which near and far effect, shadow fading and fast fading can be overcome to ensure uplink and downlink network performance, reduce network interference and improve the system quality and capacity. As a result, power control parameter values have great impact on the network. 1.1 Uplink Power Control Parameters The common configurable uplink power control parameters are listed here. 1.2 Downlink Power Control Parameters The common configurable downlink power control parameters are listed here.
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1.1 Uplink Power Control Parameters The common configurable uplink power control parameters are listed here. Table 1-1 List of uplink power control parameters N o.
Paramete r ID
Parameter Meaning
Default Value
Relevant Command
Leve l
1
PowerOffs etPpm
Power offset between the last access preamble and message control part
Signalling: -3 dB
Set: ADD PRACHTFC
Cell
ConstantV alue
Constant for PRACH initial transmit power
-20, that is, -20 dB
3
PowerRam pStep
Power increase step of random access preamble
2, that is, 2 dB
4
PreambleR etransMax
Maximum of preamble retransmissio n
8 times
5
Mmax
Max preamble loop
8 times
Default constant for initial DPCCH transmit power
-27, that is, -27 dB
2
6
1-2
DefaultCo nstantValu e
Services: -2 dB
Modify: The PRACH TFC needs to be deleted before being reconfigured.
Set: ADD PRACHBASIC
Cell
Modify: The PRACH needs to be deleted before being reconfigured.
Set: ADD RACH
Cell
Query: LST RACH Modify: MOD RACH
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Set or modify: SET FRC
RNC
Query: LST FRC
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N o.
Paramete r ID
Parameter Meaning
Default Value
Relevant Command
Leve l
7
MaxAllow edUlTxPo wer
Maximum UE uplink transmit power per service
24, that is, 24 dBm
MaxAllowedUlTxPower
Cell
MaxUlTx PowerFor Conv
Query: LST CELLSELRESEL Modify: MOD CELLSELRESEL
MaxUlTx PowerFor Str
Service-Oriented Parameters
MaxUlTx PowerForI nt
Set: ADD CELLCAC Query: LST CELLCAC Modify: MOD CELLCAC
MaxUlTx PowerFor Bac 8
RRCPRO CSRBDE LAY HHOPRO CSRBDE LAY
9
RRCPRO CPCPREA MBLE HHOPRO CPCPREA MBLE
Set: ADD CELLSELRESEL
Delay of SRB in DCH RRC process [Frame]
7
Set: ADD CELLCAC
Cell
Query: LST CELLCAC Modify: MOD CELLCAC
Delay of SRB in DCH HHO process [Frame] RRC Proc DPCCH PC preamble length [Frame]
RRC: 0 HHO: 7
HHO Proc DPCCH PC preamble length [Frame]
1.1.1 Power Offset Between Access Preamble and Message Control Part This parameter is the power offset between the last access preamble and the message control part. The access preamble power plus this offset equals the power of the control part. 1.1.2 PRACH Initial Transmit Power Constant This parameter is the constant for the UE to estimate the initial PRACH transmit power in the open loop power control process. 1.1.3 PRACH Power Ramp Step This parameter is the power increase step of the random access preambles transmitted before the UE which receives the acquisition indicator in the random access process. 1.1.4 Maximum Preamble Retransmit Attempts Issue 01 (2007-08-30)
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This parameter is the maximum number of preambles retransmission of the UE in a preamble ramping cycle. 1.1.5 Maximum Preamble Loop This parameter defines the maximum number of random access preamble loops. When the UE has transmitted the access preamble and the number of retransmission times has reached PreambleRetransMax, if the UE still has not received the capture indication, it repeats the access attempt after the specified waiting time. The maximum number of recycle cannot exceed Mmax. 1.1.6 Default DPCCH Transmit Power Constant This parameter is used by the RNC to compute the DPCCH power offset which is used by the UE to compute the initial transmit power of UL DPCCH during the open loop power control process. 1.1.7 Maximum Allowed Uplink Transmit Power of the UE The MaxAllowedULTxPower parameter determines the maximum transmit power of an UE when the UE gains access to a specific cell. This means that the cell selects UE_TXPWR_MAX_RACH in the S rule. In addition, there are four maximum UE transmit power parameters oriented to different QoS services. 1.1.8 RRC/HHO Process SRB Delay This parameter defines the delay of SRB in DCH RRC/HHO process. 1.1.9 RRC/HHO Process DPCCH Power Control Preamble Length This parameter defines the DPCCH power control preamble length in DCH RRC/HHO process.
1.1.1 Power Offset Between Access Preamble and Message Control Part This parameter is the power offset between the last access preamble and the message control part. The access preamble power plus this offset equals the power of the control part.
Parameter ID PowerOffsetPpm
Value Range –5 to 10
Physical Value Range –5 dB to 10 dB, step 1 dB
Parameter Setting According to the field test results, the recommended value during signaling transmission is set to –3 dB, and that during service transmission to –2 dB.
Impact on the Network Performance l
1-4
If the parameter value is set too low, it is likely that the signaling and the service data carried over the RACH cannot be received by UTRAN, which affects the uplink coverage. Huawei Technologies Proprietary
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If the value is too high, the uplink interference is increased, and the uplink capacity is affected.
Relevant Commands Set the parameter through ADD PRACHTFC, delete the PRACH TFC through RMV PRACHTFC before reconfiguring it. It is necessary to deactivate PRACH (DEA PRACH) and the cell (DEA CELL) before RMV PRACHTFC is executed.
1.1.2 PRACH Initial Transmit Power Constant This parameter is the constant for the UE to estimate the initial PRACH transmit power in the open loop power control process.
Parameter ID ConstantValue
Value Range -35 to -10
Physical Value Range -35 dB to -10 dB， step 1 dB
Parameter Setting The default value is -20, that is, -20 dB. This parameter is used to calculate the transmit power of the first preamble in the random access process. The formula is as follows: Preamble_Initial_Power = PCPICH DL TX power - CPICH_RSCP + UL_interference + Constant_Value where l
Preamble_Initial_Power is the preamble initial transmit power of the UE.
l
PCPICH DL TX power is downlink transmit power of the PCPICH.
l
CPICH_RSCP is the received signaling code power of the PCPICH measured by the UE.
l
UL_interference is the uplink interference, which is obtained by the UE receiving data from the broadcast channel. It is calculated at the network side and broadcast to the UE. This value is kept in the background record of the UE under test.
l
Constant_Value is obtained by the UE receiving data from the broadcast channel.
Impact on the Network Performance l
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If the value is too low, to satisfy the requirement of access power, it requires more ramps and lengthens the access period.
Relevant Commands Set this parameter through ADD PRACHBASIC and modify it through MOD PRACHUUPARAS.
1.1.3 PRACH Power Ramp Step This parameter is the power increase step of the random access preambles transmitted before the UE which receives the acquisition indicator in the random access process.
Parameter ID PowerRampStep
Value Range 1 to 8
Physical Value Range 1 dB to 8 dB, step 1 dB
Parameter Setting The default value is 2, that is 2 dB.
Impact on the Network Performance l
If this value is too high, the access process is shortened, but the probability of power waste is higher.
l
If it is too low, the access process is lengthened, but the transmitting power is saved.
It is a value should be weighed.
Relevant Commands Set this parameter through ADD PRACHBASIC， modify it through MOD PRACHUUPARAS, and query it through LST PRACH.
1.1.4 Maximum Preamble Retransmit Attempts This parameter is the maximum number of preambles retransmission of the UE in a preamble ramping cycle.
Parameter ID PreambleRetransMax
Value Range 1 to 64 1-6
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Physical Value Range 1 to 64 times
Parameter Setting The default value is 8 times. The product of this parameter and the previous PRACH Power Ramp Step determines the maximum ramp power of the UE within a preamble ramping cycle.
Impact on the Network Performance l
If this value is too low, the preamble power may fail to ramp to the required value, resulting in UE access failure.
l
If it is too high, the UE may repeatedly make access attempts by increasing the transmit power, resulting in interference to other users.
Relevant Commands Set this parameter through ADD PRACHBASIC, modify it through MOD PRACHUUPARAS, and query it through LST PRACH.
1.1.5 Maximum Preamble Loop This parameter defines the maximum number of random access preamble loops. When the UE has transmitted the access preamble and the number of retransmission times has reached PreambleRetransMax, if the UE still has not received the capture indication, it repeats the access attempt after the specified waiting time. The maximum number of recycle cannot exceed Mmax.
Parameter ID Mmax
Value Range 1 to 32
Physical Value Range None.
Parameter Setting The default value is 8.
Impact on the Network Performance l
If this parameter is too low, the UE access success rate is influenced.
l
If it is too high, the UE probably tries access attempt repeatedly within a long time, which increases the uplink interference.
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Relevant Commands Set this parameter through ADD RACH, query it through LST RACH, and modify it through MOD RACH.
1.1.6 Default DPCCH Transmit Power Constant This parameter is used by the RNC to compute the DPCCH power offset which is used by the UE to compute the initial transmit power of UL DPCCH during the open loop power control process.
Parameter ID DefaultConstantValue
Value Range -35 to -10
Physical Value Range -35 dB to -10 dB
Parameter Setting The default value is -27, that is -27 dB. The formula given in the protocol 25.331 is as follows: DPCCH_Initial_power = DPCCH_Power_offset - CPICH_RSCP Where, CPICH_RSCP is the received signaling code power of the PCPICH measured by the UE.
Impact on the Network Performance l
If this parameter is too low, the uplink synchronization at the cell verge may fail during initial link setup, which influences the uplink coverage.
l
If it is too high, it leads to instant interference to the uplink receiving, decreasing uplink receiving performance.
Relevant Commands Set or modify this parameter through SET FRC and query it through LST FRC.
1.1.7 Maximum Allowed Uplink Transmit Power of the UE The MaxAllowedULTxPower parameter determines the maximum transmit power of an UE when the UE gains access to a specific cell. This means that the cell selects UE_TXPWR_MAX_RACH in the S rule. In addition, there are four maximum UE transmit power parameters oriented to different QoS services.
Parameter ID MaxAllowedUlTxPower 1-8
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MaxUlTxPowerForConv (maximum transmit power for the session service) MaxUlTxPowerForStr (maximum transmit power for the stream service) MaxUlTxPowerForInt (maximum transmit power for the exchange service) MaxUlTxPowerForBac (maximum transmit power for the background service)
Value Range -50 to +33
Physical Value Range -50 dBm to +33 dBm, with step length as 1 dBm
Parameter Setting The setting of this parameter is based on the planned uplink network coverage. The default setting of MaxAllowedULTxPower is 21, which stands for 21 dBm. The values of the other four parameters cannot be greater than the value of MaxAllowedULTxPower. By default, the parameters MaxUlTxPowerForConv, MaxUlTxPowerForStr, MaxUlTxPowerForInt, and MaxUlTxPowerForBac are set to 24 dBm. If the capacity of a cell is restricted, this group of parameters are not a constraint for the cell. The reason is that the rapid power control function can dynamically adjust the transmit power of an UE. If the coverage of a cell is restricted, the following formula is provided according to
You can infer that
the requirement of full coverage:
Noiserise = Itotal/PN. Where: l
PUE,max represents the maximum transmit power of the UE.
l
Lmax represents the maximum path loss.
l
The character v represents the activation factor of a service.
l
Gp represents the processing gain of a service. The formula is: Gp = W/R, where W represents signal bandwidth and R represents the data transmission rate of a service.
l
Ga represents antenna gain, which is the sum of the actual antenna gain and the cable loss gain.
l
Gd represents the sum of diversity gains, such as multi-path diversity gain and receiver antenna gain.
l
PN represents the background noise.
l
Eb/Io represents the target SIR value of a service.
For the services that do not require full cell coverage, you can also use the previous formula to measure the transmit power of the UE that meets the special requirement for coverage area. If Issue 01 (2007-08-30)
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the transmit power of an UE has reached the maximum, you can use the previous formula to measure the uplink coverage area.
Impact on Network Performance If coverage area is restricted, the uplink coverage area is affected if this parameter is set to a very small value.
Relevant Commands MaxAllowedUlTxPower: use the ADD CELLSELRESEL command for configuration, the LST CELLSELRESEL command for query, and the MOD CELLSELRESEL command for modification. Service-oriented parameters: use the ADD CELLCAC command for configuration, the LST CELLCAC command for query, and the MOD CELLCAC command for modification.
1.1.8 RRC/HHO Process SRB Delay This parameter defines the delay of SRB in DCH RRC/HHO process.
Parameter ID RRCPROCSRBDELAY HHOPROCSRBDELAY
Value Range 0 to 7
Physical Value Range 0 to 7 frames, step is 1
Parameter Setting The default value of each parameter is 7. The delay of SRB involves the following signalling: PHYSICAL CHANNEL RECONFIGURATION, RADIO BEARER ESTABLISHMENT, RADIO BEARER RECONFIGURATION, RADIO BEARER RELEASE, TRANSPORT CHANNEL RECONFIGURATION, HANDOVER TO UTRAN COMMAND, RRC CONNECTION SETUP and CELL UPDATE CONFIRM.
Impact on the Network Performance The improper setting of this parameter will result in data loss and retransmission delay, which may have a negative effect on service rate and transmission delay.
Relevant Commands Set this parameter through ADD CELLCAC, query it through LST CELLCAC and modify it through MOD CELLCAC. 1-10
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1.1.9 RRC/HHO Process DPCCH Power Control Preamble Length This parameter defines the DPCCH power control preamble length in DCH RRC/HHO process.
Parameter ID RRCPROCPCPREAMBLE HHOPROCPCPREAMBLE
Value Range 0 to 7
Physical Value Range 0 to 7 times, step is 1
Parameter Setting RRCPROCPCPREAMBLE is set to 0 by default, and the default value of HHOPROCPCPREAMBLE is 7. The power control preamble involves the following signalling: PHYSICAL CHANNEL RECONFIGURATION, RADIO BEARER ESTABLISHMENT, RADIO BEARER RECONFIGURATION, RADIO BEARER RELEASE, TRANSPORT CHANNEL RECONFIGURATION, HANDOVER TO UTRAN COMMAND, RRC CONNECTION SETUP and CELL UPDATE CONFIRM. This parameter is initially used for uplink/downlink power control convergence, preventing UE from using an uncontrollable power at the beginning. When the UE transmits signals on the DPCCH, the NodeB needs a period of time to recognize the uplink signals. The length of this period of time depends on the search implementation and the transmission delay. It is useless to start the uplink transmission on DPDCH before the above process is completed. Because at that time, the data can not be correctly received and will be lost. If the AM mode is used, the retransmission may lead to a much longer delay for data transmission. The power control algorithm 1 is the only selection during the preamble period. This parameter is closely related to the DPCCH initial transmit power, the initial SIR target, the power control algorithm itself and the NodeB search ability, so it should be properly adjusted in reality.
Impact on the Network Performance The improper setting of this parameter will result in data loss and retransmission delay, which may have a negative effect on service rate and transmission delay.
Relevant Commands Set this parameter through ADD CELLCAC, query it through LST CELLCAC and modify it through MOD CELLCAC.
1.2 Downlink Power Control Parameters The common configurable downlink power control parameters are listed here. Issue 01 (2007-08-30)
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Table 1-2 List of downlink power control parameters No.
Parame ter ID
Parameter Meaning
Default Value
Relevant Command
Level
1
RlMaxD lPwr
Maximum downlink transmit power of the radio link
Refer to the table Maximum and minimum downlink transmit powers
Set: ADD CELLRLPWR Query: LST CELLRLPWR Modify: MOD CELLRLPWR
Cell
2
RlMinD lPwr
Minimum downlink transmit power of the radio link
3
PCPICH Power
Cell PCPICH transmit power
330, that is, 33 dBm
Set: ADD PCPICH Query: LST PCPICH Modify: MOD CELL
4
MaxPC PICHPo wer
Maximum PCPICH transmit power
346, that is, 34.6 dBm
5
MinPCP ICHPow er
Minimum PCPICH transmit power
313, that is, 31.3 dBm
Set: ADD PCPICH Query: LST PCPICH Modfy: MOD PCPICHPWR
1.2.1 Maximum Downlink Transmit Power of the Radio Link This parameter is the maximum downlink transmit power of radio link. It should fulfill the coverage requirement of the network planning, and the value is relative to PCPICH transmit power. 1.2.2 Minimum Downlink Transmit Power of the Radio Link This parameter is the minimum transmit power of downlink radio link. It should be considered with the maximum downlink transmit power and the dynamic range of power control, and its value is relative to PCPICH transmit power. 1.2.3 Cell PCPICH Transmit Power It is used to determine the power of Primary CPICH of a cell. The reference point is the antenna connector of NodeB. Its value is related to the downlink coverage in the network planning. 1.2.4 Maximum PCPICH Transmit Power It is used to determine the maximum transmit power of primary CPICH of a cell. The reference point is the antenna connector of NodeB. Its value is related to the downlink coverage in the network planning. 1.2.5 Minimum PCPICH Transmit Power 1-12
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It is used to determine the minimum transmit power of primary CPICH of a cell. The reference point is the antenna connector of NodeB. Its value is related to the downlink coverage in the network planning.
1.2.1 Maximum Downlink Transmit Power of the Radio Link This parameter is the maximum downlink transmit power of radio link. It should fulfill the coverage requirement of the network planning, and the value is relative to PCPICH transmit power.
Parameter ID RlMaxDlPwr
Value Range -350 to 150
Physical Value Range -35 dB to 15 dB, step 0.1 dB
Parameter Setting The service type and the service rate should be considered in parameter configuration. For an individual service, the configuration values are listed in Table 1-3. Table 1-3 Maximum and minimum downlink transmit powers Service Type (uint: bit/s)
Max. Downlink Transmit Power (in the parentheses is the dB value)
Min. Downlink Transmit Power (in the parentheses is the dB value)
12.2K AMR
0(0)
-150(-15)
64K transparent data
30(3)
-120(-12)
56K transparent data
0(0)
-150(-15)
32K transparent data
-20(-2)
-170(-17)
28.8K transparent data
-20(-2)
-170(-17)
57.6K controllable stream
-10(-1)
-160(-16)
0 stream (unidirectional)
-20(-2)
-170(-17)
384K
40(4)
-110(-11)
256K
20(2)
-130(-13)
CS
PS
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Service Type (uint: bit/s)
Max. Downlink Transmit Power (in the parentheses is the dB value)
Min. Downlink Transmit Power (in the parentheses is the dB value)
144K
0(0)
-150(-15)
128K
0(0)
-150(-15)
64K
0(0)
-150(-15)
32K
-40(-4)
-190(-19)
16K
-60(-6)
-210(-21)
8K
-80(-8)
-230(-23)
For combined services, the maximum and minimum transmit power is computed by the RNC according to the configuration of individual services.
Impact on the Network Performance l
If this parameter is too high, downlink interference may occur.
l
If it is too low, it may influence the normal functioning of downlink power control.
Relevant Commands Set this parameter through ADD CELLRLPWR, query it through LST CELLRLPWR and modify it through MOD CELLRLPWR.
1.2.2 Minimum Downlink Transmit Power of the Radio Link This parameter is the minimum transmit power of downlink radio link. It should be considered with the maximum downlink transmit power and the dynamic range of power control, and its value is relative to PCPICH transmit power.
Parameter ID RlMinDlPwr
Value Range -350 to 150
Physical Value Range -35 dB to 15 dB, step 0.1 dB
Parameter Setting Since the dynamic range of power control is set to 15 dB, this parameter is recommended as RL Max DL TX power -15 dB and refer to the related description of the sub clause Maximum Downlink Transmit Power of the Radio Link. 1-14
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Impact on the Network Performance l
If this parameter is too low, the transmit power may become too low because of incorrect estimation of SIR.
l
If it is too high, it may influence the normal functioning of downlink power control.
Relevant Commands Set this parameter through ADD CELLRLPWR, query it through LST CELLRLPWR and modify it through MOD CELLRLPWR.
1.2.3 Cell PCPICH Transmit Power It is used to determine the power of Primary CPICH of a cell. The reference point is the antenna connector of NodeB. Its value is related to the downlink coverage in the network planning.
Parameter ID PCPICHPower
Value Range -100 to 500
Physical Value Range -10 dBm to 50 dBm, step 0.1 dBm
Parameter Setting The default setting is 330, namely 33 dBm. This parameter should be set based on the actual system environment such as cell coverage (radius) and geographical environment. For the cells to be covered, the downlink coverage should be guaranteed as a premise. For the cells requiring soft handover area, this parameter should satisfy the proportion of soft handover areas stipulated in the network planning. For a cell with large coverage, the value of this parameter should be relatively high; otherwise, it should be relatively low. In a planned multi-cell environment, this parameter is definite If the value of this parameter is smaller than the planned value, coverage holes may occur when the cells are under heavy load.
Impact on the Network Performance l
If this parameter is too low, it influences directly the downlink pilot coverage range.
l
If it is too high, the downlink interference increases, and the cell capacity is decreased because a lot of system resources are occupied and the interference with the downlink traffic channels are increased.
In addition, the configuration of this parameter also has direct influence on the distribution of handover areas. Issue 01 (2007-08-30)
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Relevant Commands Set this parameter through ADD PCPICH, query it through LST PCPICH and modify it through MOD CELL.
1.2.4 Maximum PCPICH Transmit Power It is used to determine the maximum transmit power of primary CPICH of a cell. The reference point is the antenna connector of NodeB. Its value is related to the downlink coverage in the network planning.
Parameter ID MaxPCPICHPower
Value Range -100 to 500
Physical Value Range -10 dBm to 50 dBm, step 0.1 dBm
Parameter Setting The default setting is 34.6 dBm. This parameter sets the upper limit of the pilot channel transmit power. When modifying the PCPICH transmit power according to the actual requirement, ensure that this parameter is greater than the actually required PCPICH power.
Impact on the Network Performance None.
Relevant Commands Set this parameter through ADD PCPICH, query it through LST PCPICH and modify it through MOD PCPICHPWR.
1.2.5 Minimum PCPICH Transmit Power It is used to determine the minimum transmit power of primary CPICH of a cell. The reference point is the antenna connector of NodeB. Its value is related to the downlink coverage in the network planning.
Parameter ID MinPCPICHPower
Value Range -100 to 500 1-16
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1 Power Control Parameters
Physical Value Range -10 dBm to 50 dBm, step 0.1 dBm
Parameter Setting The default setting is 31.3 dBm. This parameter sets the lower limit of the pilot channel transmit power. When modifying the PCPICH transmit power according to the actual requirement, ensure that this parameter is smaller than the actually required PCPICH power. The actual system environment, such as the cell coverage range (radius) and the geographical environment should be considered while setting this parameter. If the minimum transmit power of the main common pilot physical channel is configured too small, the cell coverage will be influenced. Ensure that this parameter is set under the condition of definite soft handover area proportion, or under the condition that no coverage hole exists.
Impact on the Network Performance None.
Relevant Commands Set this parameter through ADD PCPICH, query it through LST PCPICH and modify it through MOD PCPICHPWR.
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2 Handover Parameters
2
Handover Parameters
About This Chapter Handover aims to ensure communication continuity and good communication quality. Handovers in WCDMA system are of the following types: soft handover, softer handover, intrafrequency hard handover, inter-frequency hard handover, inter-RAT hard handover and so on. Handover emerges as the important factor affecting network performance, and handover optimization is also significant in network optimization. Handover parameters are described according to the handover classification. 2.1 Intra-Frequency Handover Parameters The common configurable intra-frequency handover parameters are listed here. 2.2 Inter-Frequency Handover Parameters The common configurable inter-frequency handover parameters are listed here. 2.3 Coverage-Based Inter-RAT Handover Management Parameters The common configurable coverage-based inter-RAT handover management parameters are listed here. 2.4 Non Coverage-Based Inter-RAT Handover Management Parameters The common configurable non-coverage-based inter-RAT handover management parameters are listed here. 2.5 Blind Handover Management Parameters The common configurable blind handover management parameters are listed here. 2.6 Cell Selection and Reselection The common configurable cell selection and reselection parameters are listed here. 2.7 Neighbor Management Parameters The configurable neighbor management parameters are listed here.
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2.1 Intra-Frequency Handover Parameters The common configurable intra-frequency handover parameters are listed here. Table 2-1 List of intra-frequency handover parameters No.
Parameter ID
Parameter Meaning
Default Value
Relevant Command
Leve l
1
DivCtrlField
Softer handover combination indication switch
MAY
Set or modify: SET HOCOMM
RNC
IntraFreqFilte rCoef
Intra-Frequency measurement L3 filter coefficient
D3
3
Weight
Weighting factor
0 dB
4
IntraRelThdF or1ACS
Soft handover relative thresholds for event 1A and event 1B
1A: 6 (3 dB)
Soft handover absolute thresholds for event 1F
EcNo: -24 dB
Hysteresis related to soft handover for events 1A, 1B, 1C, 1D and 1F
1A and 1B: 0 (0 dB)
Time-to-Trigger parameters related to soft handover for events 1A, 1B, 1C, 1D and 1F
1A: D320 (320 ms)
Minimum quality threshold of soft handover
-24 dB
2
IntraRelThdF or1APS
Query: LST HOCOMM
1B: 12 (6 dB)
IntraRelThdF or1BCS IntraRelThdF or1BPS 5
IntraAblThd For1FEcNo IntraAblThd For1FRSCP
6
HystFor1A HystFor1B HystFor1C HystFor1D
For RNC Set or modify: SET INTRAFREQHO Query: LST INTRAFREQHO For Cell Set: ADD CELLINTRAFRE QHO Query: LST CELLINTRAFRE QHO Modify: MOD CELLINTRAFRE QHO
RNC Cell
RSCP: -115 dBm
1C/1D/1F: 8 (4 dB)
HystFor1F 7
TrigTime1A TrigTime1B TrigTime1C TrigTime1D TrigTime1F
8
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1B/1C/ 1D/1F: D640 (640 ms)
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2 Handover Parameters
No.
Parameter ID
Parameter Meaning
Default Value
Relevant Command
Leve l
9
CellsForbidd en1A
Affect 1A threshold flag
AFFECT
Set: ADD INTRAFREQNCE LL
NCell
CellsSorbidd en1B 10
CellIndividal Offset
Cell individual offset
0
Query: LST INTRAFREQNCE LL Modify: MOD INTRAFREQNCE LL
2.1.1 Softer Handover Combination Indication Switch This parameter determines whether the NodeB implements softer combination of radio links in soft handover. 2.1.2 Intra-Frequency Measurement L3 Filter Coefficient It is the measurement smoothing factor used for filtering the L3 intra-frequency measurement report. 2.1.3 Weighting Factor This parameter is used to identify the threshold for triggering event 1A and 1B according to the measured value of each cell in the active set. 2.1.4 Soft Handover Relative Thresholds These parameters define the difference between the quality of a cell (evaluated with the Ec/No of PCPICH at present) and the comprehensive quality of the active set (the best cell quality in case that W=0). The soft handover relative threshold parameters include IntraRelThdFor1ACS, IntraRelThdFor1APS (relative threshold for 1A) and IntraRelThdFor1BCS, IntraRelThdFor1BPS (relative threshold for 1B). 2.1.5 Event 1F Absolute Thresholds These parameters correspond to the guarantee signal strength that satisfies the basic service QoS. The absolute thresholds of soft handover include IntraAblThdFor1FEcNo and IntraAblThdFor1FRSCP (Correspond to Ec/Io and RSCP). 2.1.6 Hysteresis Related to Soft Handover These parameters represent the hysteresis values of the event 1A, 1B, 1C, 1D and 1F. 2.1.7 Time to Trigger Related to Soft Handover These parameters represent the trigger delay time of the event 1A, 1B, 1C, 1D and 1F. 2.1.8 Minimum Quality Threshold of Soft Handover When the RNC receives event 1A, 1C and 1D, it can be added to the active set only when CPICH Ec/Io of the target cell is greater than this absolute threshold. 2.1.9 Affect 1A and 1B Event Thresholds Flag Switch CellsForbidden1A affects the relevant threshold of event 1A and Switch CellsForbidden1B affects the relevant threshold of event 1B. 2.1.10 Cell Individual Offset It is the CPICH measured value offset of intra-frequency handover cells.
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2 Handover Parameters
2.1.1 Softer Handover Combination Indication Switch This parameter determines whether the NodeB implements softer combination of radio links in soft handover.
Parameter ID DivCtrlField
Value Range MAY, MUST, MUST_NOT
Physical Value Range l
Softer combination may be implemented.
l
Softer combination must be implemented.
l
Softer combination must not be implemented.
Parameter Setting The default value is MAY. There are two combination methods for uplink combination of soft handover: one is maximum ratio combination at the NodeB Rake receiver, which gives the highest combination gain; the other is selective combination at the RNC, which gives a relatively smaller combination gain. l
The default value of the indication switch is MAY, which means the NodeB decides whether to implement maximum ratio combination according to its own physical conditions
l
When MUST is selected, the NodeB is forced to carry out maximum ratio combination which is usually used in tests.
l
When MUST_NOT is selected, the NodeB is forbidden to carry out maximum ratio combination, and this method is adopted when maximum ratio combination performance of softer handover is poor.
The working status (test/normal operation) and the propagation environment should be considered when deciding whether to implement softer combination and to adopt which kind of softer combination.
Impact on the Network Performance None.
Relevant Commands Set this parameter through SET HOCOMM, and query it through LST HOCOMM.
2.1.2 Intra-Frequency Measurement L3 Filter Coefficient It is the measurement smoothing factor used for filtering the L3 intra-frequency measurement report. 2-4
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Parameter ID IntraFreqFilterCoef
Value Range Enum (D0, D1, D2, D3, D4, D5, D6, D7, D8, D9, D11, D13, D15, D17, D19), working range: Enum (D0, D1, D2, D3, D4, D5, D6, D7, D8)
Physical Value Range Enum (0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 15, 17, 19)
Parameter Setting The default value is D3. The filtering of the measurement is calculated by means of the following formula: Fn = (1 - α) · Fn - 1 + α · Mn Where, l
Fn: the updated measurement result after filtering processing.
l
Fn - 1: the old measurement result of the previous moment after filtering processing.
l
Mn: the latest measured value received from the physical layer.
l
α= (1/2)(k/2), where, k comes from filter coefficient, namely the local FilterCoef. When α is set to 1, it means there is no Layer 3 filtering.
The Layer 3 filtering should filter the random impact capability so that the filtered measured value can reflect the basic change trend of the actual measurement. Because the measured value input to Layer 3 filter is after the Layer 1 filtering, the influence of fast fading has been basically filtered; therefore, the Layer 3 filter should carry out smoothing filtering on the shadow fading and small quantity of fast fading burrs, so as to provide better measurement data for event decisions.
Impact on the Network Performance l
The greater this parameter, the stronger the smoothing effect on the signal, and the stronger the fast fading resistance capability, but the weaker the tracing capability of the signal change. If handover is not implemented in time, call drop occurs.
l
If this parameter is too low, the possibility of unnecessary soft handover and ping-pong handover increases. NOTE
As adjustment of this parameter seriously affects the entire handover performance, be cautious while setting this parameter.
Relevant Commands For the RNC-oriented intra-frequency handover algorithm parameter: set it through SET INTRAFREQHO, and query it through LST INTRAFREQHO. Issue 01 (2007-08-30)
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For the cell-oriented intra-frequency handover algorithm parameter: add it through ADD CELLINTRAFREQHO, query it through LST CELLINTRAFREQHO, and modify it through MOD CELLINTRAFREQHO.
2.1.3 Weighting Factor This parameter is used to identify the threshold for triggering event 1A and 1B according to the measured value of each cell in the active set.
Parameter ID Weight
Value Range 0 to 20
Physical Value Range 0 to 2, step 0.1
Parameter Setting The default value is 0. According to the Protocol TS25.331, in event 1A and 1B, W is defined as follows:
l
When W=0, the formula is actually the measured value of the best cell, and the determination of the relative threshold of soft handover is only related to the best cell in the active set.
l
when W=1, it can be approximately considered as the equivalent signal strength when maximum ratio combination of down links of all cells in the active is implemented.
Impact on the Network Performance l
The greater this parameter, the higher events 1A and 1B triggering thresholds obtained under the same condition, the more difficult to join the active set, and the easier to leave the active set.
l
the less this parameter, the easier to join the active set, and the more difficult to leave the active set.
Relevant Commands For RNC-oriented intra-frequency handover algorithm parameter: Set it through SET INTRAFREQHO, and query it through LST INTRAFREQHO. 2-6
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For cell-oriented intra-frequency handover algorithm parameter: Add it through ADD CELLINTRAFREQHO, query it through LST CELLINTRAFREQHO, and modify it through MOD CELLINTRAFREQHO.
2.1.4 Soft Handover Relative Thresholds These parameters define the difference between the quality of a cell (evaluated with the Ec/No of PCPICH at present) and the comprehensive quality of the active set (the best cell quality in case that W=0). The soft handover relative threshold parameters include IntraRelThdFor1ACS, IntraRelThdFor1APS (relative threshold for 1A) and IntraRelThdFor1BCS, IntraRelThdFor1BPS (relative threshold for 1B).
Parameter ID IntraRelThdFor1ACS IntraRelThdFor1APS IntraRelThdFor1BCS IntraRelThdFor1BPS
Value Range 0 to 29
Physical Value Range 0 to 14.5 dB, step 0.5 dB
Parameter Setting l
The default values of IntraRelThdFor1ACS and IntraRelThdFor1APS are 6, namely 3 dB.
l
The default values of IntraRelThdFor1BCS and IntraRelThdFor1BPS are 12, namely 6 dB.
As specified in Protocol 25.331, when CPICH Ec/No value is adopted as the measured value, the following formula is adopted for the event 1A trigger decision:
Where, l
MNew is the measured value of the cell that enters the report range;
l
CIONew is the offset of this cell;
l
Mi is the measured value of the cells in the active set;
l
NA is the number of cells in the current active set;
l
MBest is the measured value of the best cell in the active set;
l
W is the weighting value which is used for weighting the comprehensive quality of the best cell and the active set;
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2 Handover Parameters l
R1a is report range, namely the relative threshold for soft handover;
l
H1a is the hysteresis value of event 1A.
The following event is taken as the trigger condition of event 1B:
Where, l
MOld is the measured value of the cell that leaves the report range;
l
CIOOld is the offset of this cell;
l
Mi is the measured value of the cells in the active set;
l
NA is the number of cells in the current active set;
l
MBest is the measured value of the best cell in the active set;
l
W is the weighting value used for weighing the comprehensive quality of the best cell and the active set;
l
R1b is report range, namely the relative threshold for soft handover;
l
H1b is the hysteresis value of event 1B.
The selection of a relative threshold for handover corresponds directly to the soft handover proportion, and it should ensure the trouble-free implementation of smoothing handover.
Impact on the Network Performance The parameter setting determines the size of the soft handover area and the user proportion involved in soft handover. l
If the thresholds are high, the target cell joins the active set more easily, call drop occurs more difficultly, and the UE proportion in the state of soft handover increases, but the forward resources are seriously occupied.
l
If the thresholds are low, the target cell joins the active set more difficultly, the communication quality cannot be guaranteed, and the implementation of smoothing handover is affected.
Relevant Commands For RNC-oriented intra-frequency handover algorithm parameters: set them through SET INTRAFREQHO, and query them through LST INTRAFREQHO. For cell-oriented intra-frequency handover algorithm parameters: add them through ADD CELLINTRAFREQHO, query them through LST CELLINTRAFREQHO, and modify them through MOD CELLINTRAFREQHO.
2.1.5 Event 1F Absolute Thresholds These parameters correspond to the guarantee signal strength that satisfies the basic service QoS. The absolute thresholds of soft handover include IntraAblThdFor1FEcNo and IntraAblThdFor1FRSCP (Correspond to Ec/Io and RSCP). 2-8
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Parameter ID IntraAblThdFor1FEcNo IntraAblThdFor1FRSCP
Value Range IntraAblThdFor1FEcNo: -24 to 0 IntraAblThdFor1FRSCP: -155 to 25
Physical Value Range IntraAblThdFor1FEcNo: -24 dB to 0 dB, step 1 dB IntraAblThdFor1FFRSCP: -155 dBm to 25 dBm, step 1 dBm
Parameter Setting l
The default value for IntraAblThdFor1FEcNo is -24 dB.
l
The default value for IntraAblThdFor1FRSCP is -115 dBm.
Event 1F means the PCPICH measured value is less than the absolute threshold. These values are the absolute thresholds used for 1F reports in the soft handover algorithm, corresponding to the guarantee signal strength that satisfies the basic service QoS and affecting the triggering of event 1F. Event 1F is used to trigger emergency blind handover. If the optimal cell of active set reports event 1F, it indicates the active set quality is rather poor, and blind handover is triggered at this moment to make the final attempt before call drops.
Impact on the Network Performance The higher these thresholds, the more easily blind handover is triggered, and vice versa. In practice, adjust the values in accordance with the handover policy and network coverage.
Relevant Commands For RNC-oriented intra-frequency handover algorithm parameters: set them through SET INTRAFREQHO, and query them through LST INTRAFREQHO. For cell-oriented intra-frequency handover algorithm parameters: add them through ADD CELLINTRAFREQHO, query them through LST CELLINTRAFREQHO, and modify them through MOD CELLINTRAFREQHO.
2.1.6 Hysteresis Related to Soft Handover These parameters represent the hysteresis values of the event 1A, 1B, 1C, 1D and 1F.
Parameter ID HystFor1A HystFor1B Issue 01 (2007-08-30)
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HystFor1C HystFor1D HystFor1F
Value Range 0 to 15
Physical Value Range 0 to 7.5 dB, step 0.5 dB
Parameter Setting The default values: l
The 1A and event 1B hysteresis parameters are set to 0 (0 dB).
l
The others are set to 8 (4 dB).
Event 1C: cell replacement in the active set. Event 1D: In case of an active set cell, the best cell is modified; in case of a monitored set cell, it is added into the active set and the best cell is modified. l
Event 1A
The first formula is used to trigger 1A, and the second one is used to cancel 1A. Therefore, the hysteresis range is the signal fluctuation range under usual conditions, or the fluctuation range of the slow fading under the same condition. l
Event 1B
The first formula is used to trigger 1B, and the second one is used to cancel 1B. l
Event 1C MNew ≥ MInAS + H1c/2 MNew ≤ MInAS - H1c/2 The range of this value can be adjusted within 3 dB to 5 dB. Because 1C is triggered when the active set size reaches the maximum value, and the delay of handover at this time does
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not lead to bad result, the signaling interaction caused by the ping-pong effect should be reduced to the minimum in the parameter configuration. The parameter can be increased appropriately in the adjustment. l
Event 1D MNotBest ≥ MBest + H1d/2 The event cancellation formula has not been given in the protocol. According to the cancellation definitions of other events, the 1D cancellation definition can be deduced as follows: MNotBest ≤ MBest - H1d/2 The range of this value can be adjusted within 3 dB to 5 dB. Because all the handover policies are based on the best cell and the change of the best cell usually leads to the update of the measurement control, the ping-pong change and mis-decision should be reduced to the minimum in report of event 1D. The parameter can be increased appropriately in the adjustment.
l
Event 1F MNew ≤ T1f - H1f/2 MNew ≥ T1f + H1f/2 The range of this value can be adjusted within 3 dB to 5 dB. The value of this parameter is consistent with the hysteresis value for 1B.
Impact on the Network Performance l
For a UE that has entered to the soft handover area, increased hysteresis is equivalent to a reduced soft handover range.
l
For a UE that has left the soft handover area, increased hysteresis is equivalent to an increased soft handover range.
If the number of users entering the soft handover area is the same as the number of users leaving the soft handover area, there is no influence on the actual proportion of soft handover. The greater the hysteresis, the stronger the signal fluctuation resistance capability, and the better the pingpong effect suppressed. However, the response speed of the handover algorithm on signal changes is decreased. Therefore, the radio environment (slow fading characteristics), the actual handover distance and the user moving speed should be fully considered for the setting of these parameters.
Relevant Commands For RNC-oriented intra-frequency handover algorithm parameters: set them through SET INTRAFREQHO, and query them through LST INTRAFREQHO. For cell-oriented intra-frequency handover algorithm parameters: add them through ADD CELLINTRAFREQHO, query them through LST CELLINTRAFREQHO, and modify them through MOD CELLINTRAFREQHO.
2.1.7 Time to Trigger Related to Soft Handover These parameters represent the trigger delay time of the event 1A, 1B, 1C, 1D and 1F. Issue 01 (2007-08-30)
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Parameter ID TrigTime1A TrigTime1B TrigTime1C TrigTime1D TrigTime1F
Value Range Enum (D0, D10, D20, D40, D60, D80, D100, D120, D160, D200, D240, D320, D640, D1280, D2560, D5000), work range Enum (D0, D200, D240, D640, D1280, D2560, D5000)
Physical Value Range Enum (0, 10, 20, 40, 60, 80, 100, 120, 160, 200, 240, 320, 640, 1280, 2560, 5000)ms
Parameter Setting The default value for 1A is D320 （320 ms）, and the default values for other events are D640 (640 ms). The time-to-trigger mechanism is mainly used: l
To reduce the number of wrong event reports caused by burst signals.
l
To suppress ping-pong handover to some degree.
l
To reduce the influence of shadow fading on event decisions.
Layer 3 filter coefficient, hysteresis and time-to-trigger jointly overcome the interference (mainly slow fading) effect. They are used to prevent the ping-pong effect (including event reports, and active set and best cell update) caused by slow fading. In order to obtain the approximate performance, we can use different combinations of the three parameters. The interferences overcome by the three parameters are of different types: l
Filter coefficient can well overcome weak signal interference under strong signals.
l
Hysteresis is mainly used to overcome interference with the strength within a certain range, especially ping-pong handover at the verge of a cell.
l
Time-to-trigger can overcome burst signal interference effectively.
Impact on the Network Performance The greater the value of the hysteresis, the more difficult the handover occurs. However, if the value of hysteresis increases, the call drop risk increases.
Relevant Commands For RNC-oriented intra-frequency handover algorithm parameters: set them through SET INTRAFREQHO, and query them through LST INTRAFREQHO. 2-12
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For cell-oriented intra-frequency handover algorithm parameters: add them through ADD CELLINTRAFREQHO, query them through LST CELLINTRAFREQHO, and modify them through MOD CELLINTRAFREQHO.
2.1.8 Minimum Quality Threshold of Soft Handover When the RNC receives event 1A, 1C and 1D, it can be added to the active set only when CPICH Ec/Io of the target cell is greater than this absolute threshold.
Parameter ID SHOQualmin
Value Range -24 to 0
Physical Value Range -24 dB to 0 dB, step 1 dB
Parameter Setting The default value is -24, namely, -24 dB. Purpose of setting this parameter is that: If the signal added to the cell is too poor in quality, there is no apparent contribution to general quality of the active set, more downlink resources are occupied, and more TPC bit errors are introduced. On the contrary, the soft handover performance is deteriorated. Therefore, a basic quality requirement should be worked out for the added radio link. Setting of this parameter is related with the power distribution rate of public channels and the demodulation capability of UEs.
Impact on the Network Performance Adjust this parameter according to the Ec/Io that the cell soft handover area reaches as expected at network planning. l
The greater this parameter is set, the more difficult for the neighboring cell to join in the active set, but the service quality of the joining cell can be ensured.
l
The less this parameter is set, the easier for the neighboring cell to join in the active set, but a too-low parameter cannot restrict the service quality of the cell.
Relevant Commands For RNC-oriented intra-frequency handover algorithm parameter: set it through SET INTRAFREQHO, and query it through LST INTRAFREQHO. For cell-oriented intra-frequency handover algorithm parameter: add it through ADD CELLINTRAFREQHO, query it through LST CELLINTRAFREQHO, and modify it through MOD CELLINTRAFREQHO. Issue 01 (2007-08-30)
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2.1.9 Affect 1A and 1B Event Thresholds Flag Switch CellsForbidden1A affects the relevant threshold of event 1A and Switch CellsForbidden1B affects the relevant threshold of event 1B.
Parameter ID CellsForbidden1A CellsForbidden1B
Value Range NOT_AFFECT, AFFECT
Physical Value Range None.
Parameter Setting The default value is AFFECT. See the following relative threshold computation formulas of event 1A and 1B. This parameter
determines whether the measurement value Mi of corresponding cell i appears at is AFFECT, then Mi takes part in sum at computation, or else it does not.
. If it
Impact on the Network Performance When the value of W is 0, the state (On or Off) of this switch has no influence on the computation result.
Relevant Commands Add it through ADD INTRAFREQNCELL, query it through LST INTRAFREQNCELL, and modify it through MOD INTRAFREQNCELL.
2.1.10 Cell Individual Offset It is the CPICH measured value offset of intra-frequency handover cells.
Parameter ID CellIndividalOffset 2-14
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Value Range -20 to 20
Physical Value Range -10 dB to 10 dB, step 0.5 dB
Parameter Setting The default value is 0 dB. The sum of this value and the actual measured value is used in the UE event estimation. The UE uses the sum of the original cell measured value and this offset as the measurement result for the UE intra-frequency handover decision. It plays the role of shifting the cell boarder in the handover algorithm. This parameter is configured according to the actual environment in the network planning. In the neighboring cell configuration, set this parameter to a positive value if handover is expected to occur easily; otherwise, set it to a negative value. The function of this parameter is to move the cell edge and configured according to actual environment.
Impact on the Network Performance l
The greater this parameter, the more easily soft handover occurs, and the more UEs in the soft handover state, but the more forward resources occupied.
l
The less this parameter is, the more difficultly soft handover occurs, which is likely to affect the receiving quality.
Relevant Commands Add it through ADD INTRAFREQNCELL, query it through LST INTRAFREQNCELL, and modify it through MOD INTRAFREQNCELL.
2.2 Inter-Frequency Handover Parameters The common configurable inter-frequency handover parameters are listed here. Table 2-2 List of inter-frequency handover parameters No.
Parameter ID
Parameter Meaning
Default Value
Relevant Command
Level
1
InterFreqReport Mode
Inter-Frequency measurement report mode
Periodical_re porting
RNC
InterFreqMeasQ uantity
Inter-Frequency measurement quantity
BOTH
For RNC Set or modify: SET INTERFREQH OCOV Query: LST INTERFREQH OCOV For Cell
2
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No.
Parameter ID
Parameter Meaning
Default Value
Relevant Command
3
InterFreqFilterCoef
Inter-Frequency measurement filter coefficient
D3
4
WeightForUsed Freq
Frequency weighting factor
0
5
Hystfor2B
Hysteresis related to inter-frequency handover
Hystfor2B, Hystfor2D, Hystfor2F: 4 (2 dB)
Set: ADD CELLINTERFR EQHOCOV Query: LST CELLINTERFR EQHOCOV Modify: MOD CELLINTERFR EQHOCOV
Hystfor2D Hystfor2F HystforHHO
6
TrigTime2B TrigTime2D TrigTime2F
Level
HystforHHO : 0 (0 dB) Time-to-Trigger related to interfrequency hard handover
TrigTimeHHO
TrigTime2B: D0 TrigTime2D: D320 TrigTime2F: D1280 TrigTimeHH O: 0
7
InterFreqCSThd 2FRSCP InterFreqPSThd 2FRSCP InterFreqCSThd 2DRSCP
RSCP-Based inter-frequency measurement start/stop thresholds
2D: -95 dBm;
Ec/No-based inter-frequency measurement start/stop thresholds
2D: -16 dB
2F: -92 dBm
InterFreqPSThd 2DRSCP 8
InterFreqCSThd 2FEcNo InterFreqPSThd 2FEcNo InterFreqCSThd 2DEcNo
2F: -12 dB
InterFreqPSThd 2DEcNo
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No.
Parameter ID
Parameter Meaning
Default Value
9
InterFreqCovH OCSThdRSCP
Target frequency trigger threshold of inter-frequency coverage
RSCP: -92 dBm
Current used frequency quality threshold of interfrequency handover
RSCP: -92 dBm
Inter-frequency measurement minimum access thresholds
RSCP: -115 dBm
Cell individual offset
0 dB
InterFreqCovH OPSThdRSCP
Relevant Command
Level
Set: ADD INTERFREQN CELL
NCell
Ec/No: -12 dB
InterFreqCovH OCSThdEcN0 InterFreqCovH OPSThdEcN0 10
IFHOUsedFreq CSThdRSCP IFHOUsedFreq CSThdRSCP IFHOUsedFreq CSThdEcNo
Ec/No: -12 dB
IFHOUsedFreq PSThdEcNo 11
HHORSCPmin HHOEcNomin
12
CellIndividalOf fset
Ec/No: -16 dB
Query: LST INTERFREQN CELL Modify: MOD INTERFREQN CELL 13
INTERFREQR ATSWITCH
Inter-Freq and Inter-RAT coexist switch
InterFreq
Set: ADD CELLHOCOM M
Cell
Query: LST CELLHOCOM M Modify: MOD CELLHOCOM M
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No.
Parameter ID
Parameter Meaning
Default Value
Relevant Command
Level
14
CoExistMeasTh dChoice
InterFreq and InterRAT coexist measure threshold choice
COEXIST_ MEAS_THD _CHOICE_I NTERFREQ
For RNC: SET INTERFREQH OCOV
RNC/ Cell
LST INTERFREQH OCOV For Cell:ADD CELLHOCOM M LST CELLHOCOM M MOD CELLHOCOM M
15
INTERFREQM EASTIME
Inter-freq measure timer length[s]
60 s
Set: ADD CELLINTERFR EQHOCOV
Cell
Query: LST CELLINTERFR EQHOCOV Modify: MOD CELLINTERFR EQHOCOV 2.2.1 Inter-Frequency Measurement Report Mode In the inter-frequency handover based on coverage, this parameter is used to select the periodical report or event trigger mode for inter-frequency measurement report. 2.2.2 Inter-Frequency Measurement Item This parameter is used to determine whether to select Ec/No or RSCP as the measurement item. The selection is performed when the inter-frequency measurement, such as 2D/2F event and periodic measurement, is conducted in a cell. 2.2.3 Inter-Frequency Measurement Layer 3 Filter Coefficients It is the measurement smoothing factor adopted in Layer 3 inter-frequency filtering. 2.2.4 Frequency Weighting Factor This parameter is used to determine proportions of the optimal cell and other cells in the active set at calculation of the frequency integrated quality. 2.2.5 Hysteresis Related to Inter-Frequency Handover These parameters are trigger hysteresis for events 2B, 2D, 2F and hard handover (HHO). 2.2.6 Time to Trigger Related to Inter-Frequency Hard Handover These parameters are trigger delay time for events 2B, 2D, 2F and hard handover (HHO) in coverage-oriented inter frequency handover. 2.2.7 RSCP-Based Inter-Frequency Measurement Start/Stop Thresholds 2-18
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In the coverage-based inter-frequency handover, when the periodical inter-frequency measurement reporting mode is adopted, this parameter corresponds to inter-frequency measurement event absolute thresholds when RSCP is used for measurement, including event 2D absolute threshold and event 2F absolute threshold. 2.2.8 EC/No-based Inter-Frequency Measurement Start/Stop Thresholds In the coverage-based inter-frequency handover, this parameter corresponds to inter-frequency measurement event absolute thresholds when Ec/No is used for measurement. 2.2.9 Target Frequency Trigger Threshold of Inter-Frequency Coverage When the event reporting mode is adopted for inter-frequency handover in the coverage-based inter-frequency handover, this parameter is used as the mandatory threshold requirement satisfied by target frequency quality when event 2B is triggered, and it is one of the mandatory conditions for triggering event 2B. If the periodical reporting mode is adopted, this parameter is used as the absolute threshold of inter-frequency hard handover event. 2.2.10 Current Used Frequency Quality Threshold of Inter-Frequency Handover When the event reporting mode is adopted for inter-frequency handover, these parameters are used for measurement control of event 2B. Only when the quality of used frequency is poorer than this threshold, one of the mandatory conditions for triggering event 2B is satisfied. 2.2.11 Inter-Frequency Measurement Minimum Access Thresholds When the periodical reporting mode is selected for inter-frequency coverage handover, the quality measurement value of inter-frequency cell should satisfy the inter-frequency handover absolute value. Moreover, its RSCP and EcNo quality must satisfy the minimum access threshold, so inter-frequency handover may take place. The minimum access threshold corresponding to RSCP is HHORSCPmin, and that corresponding to EcNo is HHOEcNomin. 2.2.12 Cell Individual Offset It is the cell offset for inter-frequency handover. 2.2.13 Inter-Frequency/Inter-RAT Algorithm Switches This describes how to perform neighbor measurement if a cell has both inter-frequency and interRAT cells as its neighbors. 2.2.14 Inter-Frequency/Inter-RAT Measurement Threshold Choice This parameter determines what configuration parameters for events 2D and 2F should be chosen based on measurement types when a cell has both inter-frequency and inter-RAT neighbors. 2.2.15 Inter-Frequency Measure Timer Length This parameter determines what configuration parameters for events 2D and 2F should be chosen based on measurement types when a cell has both inter-frequency and inter-RAT neighbors.
2.2.1 Inter-Frequency Measurement Report Mode In the inter-frequency handover based on coverage, this parameter is used to select the periodical report or event trigger mode for inter-frequency measurement report.
Parameter ID InterFreqReportMode
Value Range Enum (Periodical_reporting, Event_trigger) Issue 01 (2007-08-30)
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Physical Value Range Periodical_reporting indicates adoption of the periodical reporting mode. Event_trigger indicates adoption of the event trigger mode.
Parameter Setting The default value is Periodical_reporting. There are two optional inter-frequency handover report modes in RNC: event report and periodical report, which are selected through the inter-frequency report mode switch. This algorithm switch is oriented to RNC configuration. l
Event report: To prevent ping-pong before and after inter-frequency handover, use 2B event (when the current in-use frequency quality is less than the absolute threshold used frequency quality threshold, the non-used frequency quality is greater than the other absolute threshold target frequency trigger threshold) as the trigger event for judging origination of interfrequency handover. As the 2B event has no event transfer period, the retry function after handover failure is not implemented, unless this cell can trigger 2B event again.
l
Periodical report: Use events 2D and 2F as the compressed mode to start and stop event, and periodically report the measurement result of inter-frequency neighboring cell in the compressed mode period. When the cell quality reported by UE is greater than the sum of an absolute threshold and the relative hysteresis, the delay trigger timer starts. If the requirement is always satisfied when the timer is expired, inter-frequency handover is started after the delay trigger timer is expired. If handover fails, handover judging continues in accordance with the inter-frequency measurement periodical report.
Impact on the Network Performance The periodical report and event report modes have their own advantages and disadvantages. At present, the traditional periodical report mode is still adopted.
Relevant Commands Parameter oriented to RNC inter-frequency handover algorithm: set it through SET INTERFREQHOCOV, and query it through LST INTERFREQHOCOV. Parameter oriented to cell inter-frequency handover algorithm: add it through ADD CELLINTERFREQHOCOV, query it through LST CELLINTERFREQHOCOV, and modify it through MOD CELLINTERFREQHOCOV.
2.2.2 Inter-Frequency Measurement Item This parameter is used to determine whether to select Ec/No or RSCP as the measurement item. The selection is performed when the inter-frequency measurement, such as 2D/2F event and periodic measurement, is conducted in a cell.
Parameter ID InterFreqMeasQuantity 2-20
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Value Range Enum (CPICH Ec_No, CPICH_RSCP, and BOTH)
Physical Value Range None
Parameter Setting The default setting is BOTH. This parameter indicates the inter-frequency measurement items that are used for inter-frequency hard handover evaluation. These items are the 2D event, the 2F event, the 2B event, and the inter-frequency measurement item used for periodic measurement. In addition, this parameter determines the measurement items used for evaluating the quality of frequencies. These frequencies are used for the 2D or 2F event stopped during the start of intersystem measurement and the 3A event. On the primary stage of the 3G coverage, the full coverage is difficult to fulfill. Some areas such as indoor area still require the GSM system to cover. Thus, the recommended value for this parameter is CPICHRSCP in this situation. In the measurement policy of the intra-frequency soft handover, the Ec/N0 of the pilot channel serves as the measurement item for handover. In the cells on the edge of bearer coverage, however, it is improper to still use Ec/N0 as the measurement item for inter-frequency hard handover. The value of the measurement item Ec/N0 is determined by the RSCP strength of the pilot signal and the downlink interference. The downlink interference of the WCDMA system are mainly the background noise and the downlink signal interference of intra-frequency cells such as local cells and neighboring cells. The downlink interference strength of intra-frequency cells are affected by path loss and slow fading, which is analogous to the fading of the signals (such as CPICHRSCP) received by an UE. On the edge of the coverage area of a bearer, the fading speed of CPICHRSCP is basically the same as the fading speed of interference when an UE in the current bearer cell moves to another bearer cell that is related to the cell currently used by the UE. Because the background noise is not affected by path loss, the fading speed of CPICH RSCP is slightly faster, depending on the strength of background noise. Thus, the UE receives the change of CPICH Ec/I0 very slowly. Both the simulation result and the actual test result prove that CPICH Ec/I0 can reach -12 dB when CPICH RSCP received by an UE reaches about -110 dBm. According to the relevant protocol, the minimum demodulation sensitivity of an UE is -117 dBm. Therefore, if only Ec/I0 is used, inter-frequency measurement may not be started in the event of a call drop. To solve this problem, you must add the selection control of the inter-frequency measurement items of cells. That is, you must use CPICH RSCP as the measurement items of inter-frequency cells for the cells on the edge of bearer coverage. For the central area of bearer coverage, you can still use CPICHEc/N0 as an inter-frequency measurement item. This can enable instant interfrequency handover to avoid call drop in the event of an intra-frequency handover failure.
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CAUTION The value BOTH ensures the higher adaptability for triggering the 2D event. It can also be used for measuring RSCP and EcN0. Thus, BOTH is regarded as the default setting. Two active sets of measurement items are delivered simultaneously. One 2D/2F measurement item is set to CPICH_EcN0. The other item is set to CPICH_RSCP. The 2D event report of either measurement item can trigger the delivery of inter-frequency measurement control.
Impact on Network Performance This parameter is set on the basis of cell location in the network and whether the inter-system neighboring cells exist.
Relevant Commands RNC-oriented inter-frequency handover algorithm parameters: use the SET INTERFREQHOCOV command for configuration and use the LST INTERFREQHOCOV command for query. Cell-oriented inter-frequency handover algorithm parameters: use the ADDCELLINTERFREQHOCOV command for addition, the LST CELLINTERFREQHOCOV command for query, and the MODCELLINTERFREQHOCOV command for modification.
2.2.3 Inter-Frequency Measurement Layer 3 Filter Coefficients It is the measurement smoothing factor adopted in Layer 3 inter-frequency filtering.
Parameter ID InterFreqFilterCoef
Value Range Enum (D0, D1, D2, D3, D4, D5, D6, D7, D8, D9, D11, D13, D15, D17, D19), working range: Enum(D0, D1, D2, D3, D4, D5, D6, D7, D8)
Physical Value Range Enum (0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 15, 17, 19)
Parameter Setting The default value is D3，namely 3. The physical meaning and measurement model of this parameter are the same as those of intrafrequency measurement; what is different is that the report cycle of inter-frequency measurement is 480 ms, while the report cycle of intra-frequency measurement is 200 ms. In inter-frequency measurement, according the different types of cells, the CPICH RSCP or CPICH Ec/No is likely to be adopted. Filter coefficient corresponding to different measurement has little difference. 2-22
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Impact on the Network Performance l
The greater this parameter, the stronger the signal smoothing effect, and the stronger the fast fading resistance capability, but the weaker the signal change tracing capability, which may result in call drop if handover is not implemented timely.
l
If the setting of this parameter is too low, the probability of unnecessary hard handover and ping-pong handover increases.
Relevant Commands For RNC-oriented inter-frequency handover algorithm parameter: set it through SET INTERFREQHOCOV, and query it through LST INTERFREQHOCOV. For cell-oriented inter-frequency handover algorithm parameter: add it through ADD CELLINTERFREQHOCOV, query it through LST CELLINTERFREQHOCOV, and modify it through MOD CELLINTERFREQHOCOV.
2.2.4 Frequency Weighting Factor This parameter is used to determine proportions of the optimal cell and other cells in the active set at calculation of the frequency integrated quality.
Parameter ID WeightForUsedFreq
Value Range 0 to 20
Physical Value Range 0 to 2, step 0.1
Parameter Setting The default value is 0, that is, only the best cell quality in the active set is used as the current frequency quality. WeightForUsedFreq is used for evaluation of events 2B, 2C, 2D and 2F. The carrier quality evaluation formula is as follows:
Where, l
Qfrequencyj is the estimated quality (dB value) of frequency j;
l
Mfrequencyj is the estimated quality (linear value) of frequency j;
l
Mij is the measurement result of cell i in the active set of frequency j;
l
NA j is the number of cells in the active set of frequency j;
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MBestj is the measurement result of optimal cell in the active set of frequency j;
l
Wj is the frequency weighting factor.
To set this parameter, refer to the setting method for intra-frequency handover weighting factor Weight.
Impact on the Network Performance l
The greater this parameter, the higher the current frequency quality estimated value under the same condition, and the more difficult inter-frequency handover occurs.
l
The less this parameter, the lower the current frequency quality estimated value, and the easier inter-frequency handover triggered.
Relevant Commands Parameter oriented to RNC inter-frequency handover algorithm: set it through SET INTERFREQHOCOV, and query it through LST INTERFREQHOCOV. Parameter oriented to cell inter-frequency handover algorithm: add it through ADD CELLINTERFREQHOCOV, query it through LST CELLINTERFREQHOCOV, and modify it through MOD CELLINTERFREQHOCOV.
2.2.5 Hysteresis Related to Inter-Frequency Handover These parameters are trigger hysteresis for events 2B, 2D, 2F and hard handover (HHO).
Parameter ID Hystfor2B Hystfor2D Hystfor2F HystforHHO
Value Range 0 to 29
Physical Value Range 0 to 14.5 dB, step 0.5 dB
Parameter Setting The default values for Hystfor2B, Hystfor2D and Hystfor2F are 4, namely 2 dB. The default value for HystforHHO is 0. Under periodic report mode, the inter-frequency measurement hysteresis is mainly used to overcome the occurrence of ping-pong handover of events 2D (the estimated quality of the current frequency is lower than the threshold) and 2F (the estimated quality of the current frequency is higher than the threshold). 2-24
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Under event report mode, the inter-frequency measurement hysteresis is mainly used to decrease the frequently handover triggered by event 2B because of radio signal changing.
Impact on the Network Performance The greater the hysteresis values, the stronger the signal fluctuation resistance capability, and the better the ping-pong effect depressed. However, the response speed of the handover algorithm to signal changes is weakened at the same time.
Relevant Commands For RNC-oriented inter-frequency handover algorithm parameters: set them through SET INTERFREQHOCOV and query them through LST INTERFREQHOCOV. For cell-oriented inter-frequency handover algorithm parameters: add them through ADD CELLINTERFREQHOCOV, query them through LST CELLINTERFREQHOCOV, and modify them through MOD CELLINTERFREQHOCOV.
2.2.6 Time to Trigger Related to Inter-Frequency Hard Handover These parameters are trigger delay time for events 2B, 2D, 2F and hard handover (HHO) in coverage-oriented inter frequency handover.
Parameter ID TrigTime2B TrigTime2D TrigTime2F TrigTimeHHO
Value Range Value range of TrigTime2B, TrigTime2D, TrigTime2F is Enum (D0, D10, D20, D40, D60, D80, D100, D120, D160, D200, D240, D320, D640, D1280, D2560, D5000), working range : Enum (D0, D200, D240, D640, D1280, D2560, D5000) Value range of TrigTimeHHO is 0 to 64000.
Physical Value Range Enum (0, 10, 20, 40, 60, 80, 100, 120, 160, 200, 240, 320, 640, 1280, 2560, 5000)ms Physical value range of TrigTimeHHO is 0 to 64000ms
Parameter Setting The default values are as follows: l
TrigTime2B: D0;
l
TrigTime2D: D320;
l
TrigTime2F: D1280;
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TrigTimeHHO:0
Impact on the Network Performance The greater the time-to-trigger values, the smaller the average handover frequency; but the increase of the time-to-trigger setting increases the risk of call drop.
Relevant Commands For RNC-oriented inter-frequency handover algorithm parameters: set them through SET INTERFREQHOCOV and query them through LST INTERFREQHOCOV. For cell-oriented inter-frequency handover algorithm parameters: add them through ADD CELLINTERFREQHOCOV, query them through LST CELLINTERFREQHOCOV, and modify them through MOD CELLINTERFREQHOCOV.
2.2.7 RSCP-Based Inter-Frequency Measurement Start/Stop Thresholds In the coverage-based inter-frequency handover, when the periodical inter-frequency measurement reporting mode is adopted, this parameter corresponds to inter-frequency measurement event absolute thresholds when RSCP is used for measurement, including event 2D absolute threshold and event 2F absolute threshold. Current Frequency Measurement Value
UE
RNC
lower than the event 2D absolute threshold
reports event 2D
sends signaling to start the compressed mode and begin inter-frequency measurement
higher than the event 2F absolute threshold
repots event 2F
sends signaling to close the compressed mode and stop inter-frequency measurement
Parameter ID Based on different bearer data domains, it can be: InterFreqCSThd2DRSCP (the CS inter-frequency measurement start threshold indicated by RSCP) InterFreqCSThd2FRSCP (the CS inter-frequency measurement close threshold indicated by RSCP) InterFreqPSThd2DRSCP (the PS inter-frequency measurement start threshold indicated by RSCP) InterFreqPSThd2FRSCP (the PS inter-frequency measurement close threshold indicated by RSCP) 2-26
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Value Range -115 to -25
Physical Value Range -115 dBm to -25 dBm, step 1 dBm
Parameter Setting l
The default values of InterFreqCSThd2DRSCP, InterFreqPSThd2DRSCP are -95, namely -95 dBm.
l
The default values of InterFreqCSThd2FRSCP, InterFreqPSThd2FRSCP are -92, namely -92 dBm.
The inter-frequency measurement start threshold (which is the compressed mode start threshold) is the most critical parameter in the inter-frequency handover policy. This set of parameters influence the proportion of users in cells entering the compressed mode and the success rate of hard handover. The following factors should be considered in the setting of this set of parameters: l
UE moving speed
l
cell radius
l
path loss
Impact on the Network Performance Events 2D and 2F are the start and stop switches of the compressed mode. When the cell is at the verge of carrier coverage, the RSCP measured values are used as the decision criterion for 2D and 2F. Therefore, lower the 2D thresholds if the compressed mode is expected to start as early as possible. To reduce the ping-pong start and stop of the compressed mode, increase appropriately the difference between the thresholds of the 2D and 2F.
Relevant Commands For RNC-oriented inter-frequency handover algorithm parameters: set them through SET INTERFREQHOCOV and query them through LST INTERFREQHOCOV. For cell-oriented inter-frequency handover algorithm parameters: add them through ADD CELLINTERFREQHOCOV, query them through LST CELLINTERFREQHOCOV, and modify them through MOD CELLINTERFREQHOCOV.
2.2.8 EC/No-based Inter-Frequency Measurement Start/Stop Thresholds In the coverage-based inter-frequency handover, this parameter corresponds to inter-frequency measurement event absolute thresholds when Ec/No is used for measurement.
Parameter ID InterFreqCSThd2DEcNo (CS inter-frequency measurement start threshold indicated by Ec/No) InterFreqCSThd2FEcNo (CS inter-frequency measurement close threshold indicated by Ec/No) InterFreqPSThd2DEcNo (PS inter-frequency measurement start threshold indicated by Ec/No) Issue 01 (2007-08-30)
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InterFreqPSThd2FEcNo (PS inter-frequency measurement close threshold indicated by Ec/No)
Value Range -24 to 0
Physical Value Range -24 dB to 0 dB, step 1 dB
Parameter Setting l
The default values of InterFreqCSThd2DecNo and InterFreqPSThd2DecNo are -16, namely -16 dB
l
The default values for InterFreqCSThd2FEcNo and InterFreqPSThd2FecNo are -12, namely -12 dB.
For the detailed descriptions, refer to 2.2.7 RSCP-Based Inter-Frequency Measurement Start/Stop Thresholds.
Impact on the Network Performance The events 2D and 2F are the compressed mode start/stop switches. When the cell is at the carrier coverage center, Ec/No measured value is taken as the decision criterion for events 2D and 2F. Therefore, set the event 2D threshold to a relatively greater value if the compressed mode is expected to start as early as possible; otherwise, set it to a relatively less value. To control the ping-pong effect of the compressed mode start/stop, increase appropriately the difference between the thresholds for events 2D and 2F.
Relevant Commands For RNC-oriented inter-frequency handover algorithm parameters: set them through SET INTERFREQHOCOV and query them through LST INTERFREQHOCOV. For cell-oriented inter-frequency handover algorithm parameters: add them through ADD CELLINTERFREQHOCOV, query them through LST CELLINTERFREQHOCOV, and modify them through MOD CELLINTERFREQHOCOV.
2.2.9 Target Frequency Trigger Threshold of Inter-Frequency Coverage When the event reporting mode is adopted for inter-frequency handover in the coverage-based inter-frequency handover, this parameter is used as the mandatory threshold requirement satisfied by target frequency quality when event 2B is triggered, and it is one of the mandatory conditions for triggering event 2B. If the periodical reporting mode is adopted, this parameter is used as the absolute threshold of inter-frequency hard handover event.
Parameter ID InterFreqCovHOCSThdEcNo (target frequency Ec/No trigger threshold of CS service) InterFreqCovHOCSThdRSCP (target frequency RSCP trigger threshold of CS service) InterFreqCovHOPSThdEcNo (target frequency Ec/No trigger threshold of PS service) 2-28
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InterFreqCovHOPSThdRSCP (target frequency RSCP trigger threshold of PS service)
Value Range InterFreqCovHOCSThdEcNo and InterFreqCovHOPSThdEcNo: -24 to 0 InterFreqCovHOCSThdRSCP and InterFreqCovHOPSThdRSCP: -115 to -25
Physical Value Range InterFreqCovHOCSThdEcNo and InterFreqCovHOPSThdEcNo: -24 dB to 0 dB InterFreqCovHOCSThdRSCP and InterFreqCovHOPSThdRSCP: -115 dBm to -25 dBm
Parameter Setting The default values of InterFreqCovHOCSThdEcNo and InterFreqCovHOPSThdEcNo are -12 dB. The default values of InterFreqCovHOCSThdRSCP and InterFreqCovHOPSThdRSCP are -92 dBm.
Impact on the Network Performance The greater the parameters are, the more difficult hard handover occurs.
Relevant Commands For parameters oriented to RNC inter-frequency handover algorithm: set them through SET INTERFREQHOCOV, and query them through LST INTERFREQHOCOV. For parameters oriented to cell inter-frequency handover algorithm: add them through ADD CELLINTERFREQHOCOV, query them through LST CELLINTERFREQHOCOV, and modify them through MOD CELLINTERFREQHOCOV.
2.2.10 Current Used Frequency Quality Threshold of InterFrequency Handover When the event reporting mode is adopted for inter-frequency handover, these parameters are used for measurement control of event 2B. Only when the quality of used frequency is poorer than this threshold, one of the mandatory conditions for triggering event 2B is satisfied.
Parameter ID Based on different inter-frequency measurement quantities in use and different borne services, it can be: IFHOUsedFreqCSThdEcNo (used frequency Ec/No quality threshold of CS service) IFHOUsedFreqPSThdEcNo (used frequency Ec/No quality threshold of PS service) IFHOUsedFreqCSThdRSCP (used frequency RSCP quality threshold of CS service) IFHOUsedFreqCSThdRSCP (used frequency RSCP quality threshold of PS service) Issue 01 (2007-08-30)
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Value Range IFHOUsedFreqCSThdEcNo and IFHOUsedFreqPSThdEcNo: -24 to 0 IFHOUsedFreqCSThdRSCP and IFHOUsedFreqCSThdRSCP: -115 to -25
Physical Value Range IFHOUsedFreqCSThdECNo and IFHOUsedFreqPSThdECNo: -24 dB to 0 dB, step 1 dB IFHOUsedFreqCSThdRSCP and IFHOUsedFreqCSThdRSCP: -115 dBm to -25 dBm, step 1 dBm
Parameter Setting The default values of IFHOUsedFreqCSThdEcNo and IFHOUsedFreqPSThdEcNo are -12 dB. The default values of IFHOUsedFreqCSThdRSCP and IFHOUsedFreqCSThdRSCP are -92 dBm. Factors to be considered while setting these parameters: The cell signal quality of current frequency is poor and cannot better satisfy the coverage requirement of current service. After handover is completed, it is hard to hand over to the current used frequency cell again even inter-frequency measurement is started again. In other words, these parameters should be set less than the trigger threshold of event 2F, or equal to the threshold of event 2D.
Impact on the Network Performance Higher values of these parameters get event 2B to be more easily triggered.
Relevant Commands For parameters oriented to RNC inter-frequency handover algorithm: set them through SET INTERFREQHOCOV, and query them through LST INTERFREQHOCOV. For parameters oriented to cell inter-frequency handover algorithm: add them through ADD CELLINTERFREQHOCOV, query them through LST CELLINTERFREQHOCOV, and modify them through MOD CELLINTERFREQHOCOV.
2.2.11 Inter-Frequency Measurement Minimum Access Thresholds When the periodical reporting mode is selected for inter-frequency coverage handover, the quality measurement value of inter-frequency cell should satisfy the inter-frequency handover absolute value. Moreover, its RSCP and EcNo quality must satisfy the minimum access threshold, so inter-frequency handover may take place. The minimum access threshold corresponding to RSCP is HHORSCPmin, and that corresponding to EcNo is HHOEcNomin.
Parameter ID HHORSCPmin HHOEcNomin 2-30
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Value Range HHOEcNomin: -24 to 0 HHORSCPmin: -115 to -25
Physical Value Range HHOEcNomin: -24 dB to 0 dB, step 1 dB HHORSCPmin: -115 dBm to -25 dBm, step 1 dBm
Parameter Setting The default value of HHOEcNomin is -16 dB, and the default value of HHORSCPmin is -115 dBm. The minimum quality requirements for EcNo and RSCP ensure that the target cell quality is not too poor.
Impact on the Network Performance l
The greater these parameters, the more difficult the inter-frequency handover occurs, but the quality after handover can be ensured.
l
The less these parameters, the looser the inter-frequency handover requirement, but it may lead to handover to a poor cell and occurrence of ping-pong handover.
Relevant Commands For parameters oriented to RNC inter-frequency handover algorithm: set them through SET INTERFREQHOCOV, and query them through LST INTERFREQHOCOV. For parameters oriented to cell inter-frequency handover algorithm: add them through ADD CELLINTERFREQHOCOV, query them through LST CELLINTERFREQHOCOV, and modify them through MOD CELLINTERFREQHOCOV.
2.2.12 Cell Individual Offset It is the cell offset for inter-frequency handover.
Parameter ID CellIndividalOffset
Value Range -20 to 20
Physical Value Range -10 dB to 10 dB, step 0.5 dB
Parameter Setting The default value is 0 dB. Issue 01 (2007-08-30)
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It is the CPICH measurement offset of neighboring cell. The UE uses the sum of the original measurement value of the cell and this offset as the measurement result for the UE interfrequency handover decision. This parameter plays the role of moving the cell boarder in the handover algorithm. This parameter is configured according to the actual environment in the network planning. In the neighboring cell configuration, set this parameter to a positive value if handover is expected to occur easily; otherwise, set it to a negative value.
Impact on the Network Performance l
The greater this parameter, the more easily inter-frequency hard handover occurs.
l
The less this parameter, the more difficult hard handover occurs.
Relevant Commands Set this parameter through ADD INTERFREQNCELL, query it through LST INTERFREQNCELL, and modify it through MOD INTERFREQNCELL.
2.2.13 Inter-Frequency/Inter-RAT Algorithm Switches This describes how to perform neighbor measurement if a cell has both inter-frequency and interRAT cells as its neighbors.
Parameter ID InterFreqRATSwitch
Value Range Enum(InterFreq, InterRAT, SimInterFreqRAT)
Physical Value Range Only the inter-frequency neighbors are measured. Only the inter-RAT neighbors are measured. The inter-frequency neighbors and the inter-RAT neighbors are measured at the same time.
Parameter Setting The default setting is InterFreq. For a cell having both inter-frequency neighbors and inter-RAT neighbors, configure the cell based on the actual handover policy. InterFreq: measures only the inter-frequency cells and conducts inter-frequency handover. InterRAT: conducts only the inter-RAT handover for the cells only in the GSM network. SimInterFreqRAT: measures the inter-frequency and inter-RAT cells simultaneously. For the SimInterFreqRAT, the time for handover depends on what cells have the highest handover priority. The algorithm switch is invalid when only inter-frequency cells or inter-RAT cells are available. 2-32
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Impact on the Network Performance This parameter determines the cell handover policy in case inter-frequency neighbors co-exist with inter-RAT neighbors. Configure this parameter for each cell.
Relevant Commands This parameter is a cell-oriented handover global parameter. Set this parameter through ADD CELLHOCOMM, query it through LST CELLHOCOMM, and modify it through MOD CELLHOCOMM.
2.2.14 Inter-Frequency/Inter-RAT Measurement Threshold Choice This parameter determines what configuration parameters for events 2D and 2F should be chosen based on measurement types when a cell has both inter-frequency and inter-RAT neighbors.
Parameter ID CoExistMeasThdChoice
Value Range COEXIST_MEAS_THD_CHOICE_INTERFREQ, COEXIST_MEAS_THD_CHOICE_INTERRAT
Physical Value Range COEXIST_MEAS_THD_CHOICE_INTERFREQ: indicates that 2D and 2F measurement threshold parameters orientated to inter-frequency are chosen as thresholds for cell subscribers to enable or disable the compress mode. COEXIST_MEAS_THD_CHOICE_INTERRAT: indicates that 2D and 2F measurement threshold parameters orientated to inter-RAT are chosen as thresholds for cell subscribers to enable or disable the compress mode.
Parameter Setting The default setting is COEXIST_MEAS_THD_CHOICE_INTERFREQ. During the setting, take into account the following items: Thresholds for 2D and 2F events in inter-frequency and inter-RAT systems, thresholds for the inter-frequency or inter-RAT handover, and current handover policies. For instance, you plan to choose inter-frequency neighbors when the inter-frequency and inter-RAT neighbors coexist, you can choose the measurement threshold parameters for the inter-frequency in case the threshold for an inter-RAT 2D event is greater than that for an inter-frequency 2D event.
Impact on the Network Performance Set based on actual network handover policies.
Relevant Commands Parameter oriented to the RNC inter-frequency handover algorithm: set it through SET HOCOMM and query it through LST HOCOMM. Issue 01 (2007-08-30)
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Parameter oriented to cell handover algorithm: add it through ADD CELLHOCOMM, query it through LST CELLHOCOMM, and modify it through MOD CELLHOCOMM.
2.2.15 Inter-Frequency Measure Timer Length This parameter determines what configuration parameters for events 2D and 2F should be chosen based on measurement types when a cell has both inter-frequency and inter-RAT neighbors.
Parameter ID INTERFREQMEASTIME
Value Range Integer: 1 to 512
Physical Value Range Integer: 1 s to 512 s
Parameter Setting The default value is 60 s. The expiration length for inter-frequency measurement timer. The system stops inter-frequency measurement and disables the compressed mode if enabled, if no inter-frequency handover occurs upon expiry of the inter-frequency measurement timer. This parameter is used to prevent a cell from being in inter-frequency measurement state for a long time, for the cell cannot find a target cell that meets the measurement requirements.
Impact on the Network Performance This parameter is used to reduce the impact on serving cells by shortening the time for mode compression. Closing the compress mode in advance results in UE's failure to initiate an inter-frequency handover. The coverage-based inter-frequency handover may lead to call drops.
Relevant Commands Parameter oriented to the cell inter-frequency handover algorithm, add it through ADD CELLINTERFREQHOCOV, query it through LST CELLINTERFREQHOCOV, and modify it through MOD CELLINTERFREQHOCOV.
2.3 Coverage-Based Inter-RAT Handover Management Parameters The common configurable coverage-based inter-RAT handover management parameters are listed here. 2-34
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Table 2-3 List of coverage-based inter-RAT handover management parameters No.
Parameter ID
Parameter Meaning
Default Value
Relevant Command
Level
1
InterRATFilte rCoef
Inter-RAT measurement filter coefficient
D3
For RNC Set or modify: SET INTERRATHOCO V Query: LST INTERRATHOCO V For Cell Set: ADD CELLINTERRAT HOCOV Query: LST CELLINTERRAT HOCOV Modify: MOD CELLINTERRAT HOCOV
RNC
2D2FFilterCo ef 2
InterRATRep ortMode
Inter-RAT measurement report mode
Periodical_r eporting
3
WeightForUse dFreq
Frequency weighting factor
0
4
InterPeriodRe portInterval
Inter-RAT period report interval
D1000 (1000 ms)
5
BSICVerify
BSIC verify selection switch
Require
6
2D2FMeasQu antity
Inter-RAT measurement quantity
2D2FMeas Quantity: BOTH
3AMeasQuant ity
7
InterRATCST hd2DRSCP InterRATPST hd2DRSCP InterRATCST hd2FRSCP InterRATPST hd2FRSCP
Cell
3AMeasQu antity: CPICH_RS CP RSCP-Based inter-RAT measurement start/stop thresholds
InterRatCS Thd2DRscp : -100 (dBm) InterRatPST hd2DRscp: -110 (dBm) InterRatCS Thd2FRscp: -97 (dBm) InterRatPST hd2FRscp: -107 (dBm)
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No.
Parameter ID
Parameter Meaning
Default Value
8
InterRATCST hd2DEcN0
Ec/No-Based inter-RAT measurement start/stop thresholds
InterRATC SThd2DEc N0: -14 (dB)
InterRATPST hd2DEcN0 InterRATCST hd2FEcN0
Relevant Command
Level
InterRATPS Thd2DEcN 0: -15 (dB) InterRATC SThd2FEcN 0: -12 (dB)
InterRATPST hd2FEcN0
InterRATPS Thd2FEcN0 : -13 (dB) 9
InterRATCov HOCSThd InterRATCov HOPSThd
10
TrigTime2D TrigTime2F TrigTime3A
Inter-RAT handover judging thresholds
16, that is, -95 dBm
Time-to-Trigger related to interRAT handover event
TRIGTIME 2D: D320 TRIGTIME 2F: D1280 TRIGTIME 3A: D0
11
Hystfor3A Hystfor2D Hystfor2F
Hysteresis related with inter-RAT handover coverage
2D/2F/3A: 4 (2 dB)
HystforInterR AT
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HystforInter RAT: 0(0 dB)
12
TimeToTrigF orVerify
Time-to-Trigger for verified GSM cell
0, that is, handover immediately
13
TimeToTrigF orNonVerify
Time-to-Trigger for non-verified GSM cell
65535, that is, handover to nonverified GSM cell is forbidden
14
PenaltyTimef orInterRATH O
Penalty time for inter-RAT handover
30 s
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No.
Parameter ID
Parameter Meaning
Default Value
Relevant Command
Level
15
CellIndividal Offset
Cell individual offset
0 dB
Set: ADD GSMNCELL
NCell
Query: LST GSMNCELL Modify: MOD GSMNCELL 16
IRHOUsedFre qCSThdEcN0 IRHOUsedFre qPSThdEcN0 IRHOUsedFre qCSThdRSCP IRHOUsedFre qPSThdRSCP
17
InterRATMea sTime
Inter-RAT CS used frequency trigger Ec/No threshold
IRHOUsed FreqCsThd EcN0: -12 (dB)
Inter-RAT PS used frequency trigger Ec/No threshold
IRHOUsed FreqPsThdE cN0: -13 (dB)
Inter-RAT CS used frequency trigger RSCP threshold
IRHOUsed FreqCsThd Rscp: -97 (dBm)
Inter-RAT PS used frequency trigger RSCP threshold
IRHOUsed FreqPsThd Rscp: -107 (dBm)
Inter-RAT measure timer length
60 s
For RNC Set or modify: SET INTERRATHOCO V Query: LST INTERRATHOCO V For Cell Set: ADD CELLINTERRAT HOCOV Query: LST CELLINTERRAT HOCOV Modify: MOD CELLINTERRAT HOCOV
RNC Cell
2.3.1 Inter-RAT Measurement L3 Filter Coefficients In the inter-RAT handover based on coverage, these parameters refer to the measurement smooth coefficient adopted at L3 inter-RAT measurement report filtering and the measurement smooth coefficient adopted at events 2D and 2F report. 2.3.2 Inter-RAT Measurement Report Mode In the coverage-based inter-RAT handover, this parameter is used to select the periodical report or event trigger mode for inter-RAT measurement report. 2.3.3 Frequency Weighting Factor This parameter is used to determine proportions of the optimal cell and other cells in the active set at calculation of the frequency integrated quality. 2.3.4 Inter-RAT Period Report Interval The parameter is used to determine the measurement report interval when the inter-RAT measurement report mode chooses Periodical_Reporting. 2.3.5 BSIC Verify Selection Switch This parameter is used to control the inter-RAT measurement report cell. If it is set to Require, report is allowed only after the measured GSM cell identity code (BSIC) is correctly decoded. If it is set to Not_Require, then all the measured cells can be reported so long as they satisfy the above report condition, regardless of their BSICs correctly decoded or not. Issue 01 (2007-08-30)
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2.3.6 Inter-RAT Measurement Quantity Parameter 2D2FMeasQuantity is used to configure events 2D and 2F measurement quantity for starting and stopping inter-RAT measurement, including EcNo and RSCP. Parameter 3AMeasQuantity is used to configure event 3A measurement quantity for inter-RAT measurement, including EcNo and RSCP. 2.3.7 RSCP-Based Inter-RAT Measurement Start/Stop Thresholds This set of parameters correspond to the absolute thresholds of the inter-RAT measurement events when RSCP is used for measurement. 2.3.8 Ec/No-Based Inter-RAT Measurement Start/Stop Thresholds This set of parameters correspond to the absolute thresholds of the inter-RAT measurement event when Ec/No is used for measurement. 2.3.9 Inter-RAT Handover Judging Thresholds Inter-RAT handover judging thresholds involve the inter-RAT CS service handover judging threshold InterRATCovHOCSThd and the inter-RAT PS service handover judging threshold InterRATCovHOPSThd. 2.3.10 Time to Trigger Related to Inter-RAT Handover In coverage-oriented inter frequency handover, the time-to-trigger parameters include time-totrigger for 2D (TrigTime2D), time-to-trigger for 2F (TrigTime2F) and time-to-trigger for 3A (TrigTime3A). 2.3.11 Hysteresis Related to Coverage-Based Inter-RAT Handover In the coverage-based inter-RAT handover, hystereses triggered by events include 3A hysteresis Hystfor3A, 2D hysteresis Hystfor2D, 2F hysteresis Hystfor2F, and inter-RAT handover hysteresis HystforInterRAT. 2.3.12 Time to Trigger for Verified GSM Cell This parameter refers to the delay trigger time of GSM cell verified already by the BS identity code BSIC. If the signal quality of GSM neighboring cell always satisfies the inter-RAT handover judging condition in the time range stipulated by this parameter value, and the GSM neighboring cell is in the verified state, the network starts the inter-RAT handover process. 2.3.13 Time to Trigger for Non-verified GSM Cell This parameter represents the delay time for triggering a GSM cell unacknowledged by BSIC. In the period specified by this parameter, if the signal quality of an adjacent GSM cell meets the requirement for inter-RAT handover and this cell is unacknowledged, the network starts interRAT handover. 2.3.14 Penalty Time for Inter-RAT Handover For inter-RAT handover failure to the GSM cell, possibly it is refused because the load of this cell is heavy. Therefore, no inter-RAT handover request is sent to this cell in the time range stipulated by this parameter value. 2.3.15 Cell Individual Offset This parameter refers to the inter-RAT handover cell individual offset. 2.3.16 Current Used Frequency Quality Threshold of Inter-RAT Handover This parameter is used for measurement control of event 3A when the event reporting mode is adopted for the inter-RAT measurement. Only when the quality of used frequency is poorer than this threshold, one of the mandatory conditions for triggering event 3A is satisfied. 2.3.17 Inter-RAT Measure Timer Length This parameter defines the valid time for inter-RAT measurement. If the timer cannot find an appropriate inter-RAT cell to initiate the inter-RAT handover, for instance, the event 3A report is not received or all period reports cannot satisfy the trigger condition for the inter-RAT 2-38
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handover, the RNC disables the compress mode to release the resources for inter-RAT measurement and waits for the inter-RAT measurement of the next round.
2.3.1 Inter-RAT Measurement L3 Filter Coefficients In the inter-RAT handover based on coverage, these parameters refer to the measurement smooth coefficient adopted at L3 inter-RAT measurement report filtering and the measurement smooth coefficient adopted at events 2D and 2F report.
Parameter ID InterRATFilterCoef 2D2FFilterCoef
Value Range Enum (D0, D1, D2, D3, D4, D5, D6, D7, D8, D9, D11, D13, D15, D17, D19)
Physical Value Range Enum (0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 15, 17, 19)
Parameter Setting The default values for both InterRATFilterCoef and 2D2FFilterCoef are D3, namely 3. The physical meaning and measurement model of these parameters are the same as those of inter-frequency measurement, and the reporting periods are 480 ms. For the specific analysis, refer to 2.1.2 Intra-Frequency Measurement L3 Filter Coefficient and 2.2.3 InterFrequency Measurement Layer 3 Filter Coefficients.
Impact on the Network Performance The greater these parameter, the stronger the effect on signal smoothness, the stronger the fastfading resistance capability, but the weaker the tracing capability for signal change, and call drops due to handover failure. If these values are set too low, unnecessary inter-RAT handover occurs.
Relevant Commands For parameters oriented to RNC inter-RAT handover algorithm: set them through SET INTERRATHOCOV, and query them through LST INTERRATHOCOV. For parameters oriented to cell inter-RAT handover algorithm: add them through ADD CELLINTERRATHOCOV, query them through LST CELLINTERRATHOCOV, and modify them through MOD CELLINTERRATHOCOV.
2.3.2 Inter-RAT Measurement Report Mode In the coverage-based inter-RAT handover, this parameter is used to select the periodical report or event trigger mode for inter-RAT measurement report. Issue 01 (2007-08-30)
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Parameter ID InterRATReportMode
Value Range Enum (Periodical_reporting, Event_trigger)
Physical Value Range Periodical_reporting indicates adoption of the periodical reporting mode. Event_trigger indicates adoption of the event trigger mode.
Parameter Setting The default value is Periodical_reporting. There are two optional inter-frequency handover report modes in RNC: event report and periodical report, which are selected through the inter-RAT report mode switch. This algorithm switch is oriented to RNC configuration. l
Event report: To prevent ping-pong before and after inter-RAT handover, event 3A (the current used frequency quality is lower than the absolute threshold, and the GSM cell level is higher than the other absolute threshold) is used as the trigger event for judging origination of inter-RAT handover. To improve the handover success ratio, the GSM cell BSIC of the trigger event must be decoded correctly by EU. As the event 3A has no event transfer period, the retry function after handover failure is not implemented, unless this cell can trigger event 3A again.
l
Periodical report: When the level of the GSM cell reported by UE is higher than the inter-RAT event 2D absolute threshold + hysteresis, it starts the delay trigger timer. If the clock satisfies requirement during timer expires, start the inter-frequency handover after the delay trigger timer is expires. If handover fails, retry in accordance with the inter-RAT measurement periodical report.
Impact on the Network Performance The periodical report and event report modes have their own advantages and disadvantages. At present, the traditional periodical report mode is still adopted.
Relevant Commands For parameter oriented to RNC inter-RAT handover algorithm: set it through SET INTERRATHOCOV, and query it through LST INTERRATHOCOV. For parameter oriented to cell inter-RAT handover algorithm: add it through ADD CELLINTERRATHOCOV, query it through LST CELLINTERRATHOCOV, and modify it through MOD CELLINTERRATHOCOV.
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2.3.3 Frequency Weighting Factor This parameter is used to determine proportions of the optimal cell and other cells in the active set at calculation of the frequency integrated quality.
Parameter ID WeightForUsedFreq
Value Range 0 to 20
Physical Value Range 0 to 2, step 0.1
Parameter Setting The default value is 0, that is, only the best cell quality in the active set is used as the current frequency quality. WeightForUsedFreq is used for evaluation of events 2D and 2F. The carrier quality evaluation formula is as follows:
Here, l
Qfrequencyj is the estimated quality (dB value) of frequency j.
l
Mfrequencyj is the estimated quality (linear value) of frequency j.
l
Mij is the measurement result of cell i in the active set of frequency j.
l
NAj is the number of cells in the active set of frequency j.
l
MBestj is the measurement result of optimal cell in the active set of frequency j.
l
Wj is the frequency weighting factor.
For setting this parameter, refer to the setting method for intra-frequency handover weighting factor.
Impact on the Network Performance l
The greater this parameter is, the higher the current frequency quality estimated value is calculated under the same condition, and the more difficult the inter-frequency handover occurs.
l
The lower the parameter is, the lower the current frequency quality estimated value is, and the easier the inter-frequency handover is triggered.
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Relevant Commands Parameter oriented to RNC inter-RAT handover algorithm: set it through SET INTERRATHOCOV, and query it through LST INTERRATHOCOV. Parameter oriented to cell inter-RAT handover algorithm: add it through ADD CELLINTERRATHOCOV, query it through LST CELLINTERRATHOCOV, and modify it through MOD CELLINTERRATHOCOV.
2.3.4 Inter-RAT Period Report Interval The parameter is used to determine the measurement report interval when the inter-RAT measurement report mode chooses Periodical_Reporting.
Parameter ID InterRATPeriodReportInterval
Value Range Enum (NON_PERIODIC_REPORT, D250, D500, D1000, D2000, D3000, D4000, D6000, D8000, D12000, D16000, D20000, D24000, D28000, D32000, D64000)
Physical Value Range Enum (NON_PERIODIC_REPORT, 250 ms, 500 ms, 1000 ms, 2000 ms, 3000 ms, 4000 ms, 6000 ms, 8000 ms, 12000 ms, 16000 ms, 20000 ms, 24000 ms, 28000 ms, 32000 ms, 64000 ms)
Parameter Setting The default value is D1000, namely, 1000 ms. For the GSM RSSI measurement period is 480 ms, this parameter shall be greater than 480 ms. If this parameter is too high, the handover judging time shall be long.
Impact on the Network Performance The bigger the report interval value is, the smaller the number of measurement report will be; but the increase of the report interval setting will increase the risk of call drop.
Relevant Commands Parameter oriented to RNC inter–RAT handover algorithm: set it through SET INTERRATHOCOV, and query it through LST INTERRATHOCOV. Parameter oriented to cell inter–RAT handover algorithm: add it through ADD CELLINTERRATHOCOV, query it through LST CELLINTERRATHOCOV, and modify it through MOD CELLINTERRATHOCOV.
2.3.5 BSIC Verify Selection Switch This parameter is used to control the inter-RAT measurement report cell. If it is set to Require, report is allowed only after the measured GSM cell identity code (BSIC) is correctly decoded. If it is set to Not_Require, then all the measured cells can be reported so long as they satisfy the above report condition, regardless of their BSICs correctly decoded or not. 2-42
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Parameter ID BSICVerify
Value Range Enum (Require, Not_Require)
Physical Value Range None.
Parameter Setting The default value is Require. This parameter is valid for both periodical report and event report. To ensure handover reliability, it is recommended to make a report after BSIC verification.
Impact on the Network Performance When it is set to Not_Require, it is easier for handover to occur, but the handover is not as reliable as in the Require mode.
Relevant Commands For parameter oriented to RNC inter-RAT handover algorithm: set it through SET INTERRATHOCOV, and query it through LST INTERRATHOCOV. For parameter oriented to cell inter-RAT handover algorithm: add it through ADD CELLINTERRATHOCOV, query it through LST CELLINTERRATHOCOV, and modify it through MOD CELLINTERRATHOCOV.
2.3.6 Inter-RAT Measurement Quantity Parameter 2D2FMeasQuantity is used to configure events 2D and 2F measurement quantity for starting and stopping inter-RAT measurement, including EcNo and RSCP. Parameter 3AMeasQuantity is used to configure event 3A measurement quantity for inter-RAT measurement, including EcNo and RSCP.
Parameter ID 2D2FMeasQuantity 3AMeasQuantity
Value Range 2D2FMeasQuantity: Enum (CPICH_EcNo, CPICH_RSCP, BOTH) 3AMeasQuantity: Enum (CPICH_EcNo, CPICH_RSCP)
Physical Value Range None. Issue 01 (2007-08-30)
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Parameter Setting The default value for 2D2FMeasQuantity is BOTH. Both the CPICH_Ec/No and the CPICH_RSCP are criteria for the Active Set Quality. The RNC sends Active Set Measurement control for each measurement quantity. Event 2D and Event 2F are only valid for corresponding measurement quantity. The default value for 3AMeasQuantity is CPICH_RSCP, which means to use the RSCP measurement quantity for event 3A measurement. The physical unit is dBm.
Impact on the Network Performance Set it based on the cell location in the network.
Relevant Commands For parameters oriented to RNC inter-RAT handover algorithm: set them through SET INTERRATHOCOV, and query them through LST INTERRATHOCOV. For parameters oriented to cell inter-RAT handover algorithm: add them through ADD CELLINTERRATHOCOV, query them through LST CELLINTERRATHOCOV, and modify them through MOD CELLINTERRATHOCOV.
2.3.7 RSCP-Based Inter-RAT Measurement Start/Stop Thresholds This set of parameters correspond to the absolute thresholds of the inter-RAT measurement events when RSCP is used for measurement.
Parameter ID InterRATCSThd2DRSCP (the CS inter-RAT measurement start threshold expressed with RSCP) InterRATPSThd2DRSCP (the PS inter-RAT measurement start threshold expressed with RSCP) InterRATCSThd2FRSCP (the CS inter-RAT measurement stop threshold expressed with RSCP) InterRATPSThd2FRSCP (the PS inter-RAT measurement stop threshold expressed with RSCP)
Value Range -115 to -25
Physical Value Range -115 dBm to -25 dBm, step 1 dBm
Parameter Setting The default values are as follows:
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l
InterRatCSThd2DRSCP is -100 dBm;
l
InterRatCSThd2FRSCP is -97 dBm;
l
InterRatPSThd2DRSCP is -110 dBm; Huawei Technologies Proprietary
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InterRatPSThd2FRSCP is -107dBm.
For the detailed descriptions, refer to 2.2.7 RSCP-Based Inter-Frequency Measurement Start/Stop Thresholds. For multiRAB services, use the configuration of CS service if there exits CS service.
Impact on the Network Performance Events 2D and 2F are the compressed mode start/stop switches. Because different service types may have different requirements on the signal quality and different inter-RAT handover policies to be adopted, the inter-RAT measurement start/stop thresholds are classified here according to CS, PS and signaling. When a cell is at the verger of carrier frequency coverage, it uses RSCP measurement values as the decision criterion for 2D and 2F. Set the event 2D thresholds to a greater value if the compressed mode is expected to start as early as possible; otherwise set it to a lower value. To reduce ping-pong start/stop of the compressed mode, increase appropriately the difference between the 2D and 2F thresholds.
Relevant Commands For parameters oriented to RNC inter-RAT handover algorithm: set them through SET INTERRATHOCOV, and query them through LST INTERRATHOCOV. For parameters oriented to cell inter-RAT handover algorithm: add them through ADD CELLINTERRATHOCOV, query them through LST CELLINTERRATHOCOV, and modify them through MOD CELLINTERRATHOCOV.
2.3.8 Ec/No-Based Inter-RAT Measurement Start/Stop Thresholds This set of parameters correspond to the absolute thresholds of the inter-RAT measurement event when Ec/No is used for measurement.
Parameter ID InterRATCSThd2DEcNo (the CS inter-RAT measurement start threshold expressed with Ec/ No) InterRATPSThd2DEcNo (the PS inter-RAT measurement start threshold expressed with Ec/ No) InterRATCSThd2FEcNo (the CS inter-RAT measurement stop threshold expressed with Ec/ No) InterRATPSThd2FEcNo (the PS inter-RAT measurement stop threshold expressed with Ec/No)
Value Range -24 to 0
Physical Value Range -24 dB to 0 dB, step 1 dB Issue 01 (2007-08-30)
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Parameter Setting The default values are as follows: l
InterRATCSThd2DEcNo is -14 dB;
l
InterRATCSThd2FEcNo is -12dB;
l
InterRATPSThd2DEcNo is -15dB;
l
InterRATPSThd2FEcNo is -13dB.
For the detailed descriptions, refer to 2.2.7 RSCP-Based Inter-Frequency Measurement Start/Stop Thresholds. For multiRAB service, use the configuration of CS service if there exists CS service.
Impact on the Network Performance Events 2D and 2F are the compressed mode start/stop switches. Because different service types may require different signal qualities and different inter-RAT handover policies, the inter-RAT measurement start/stop thresholds are classified here according to CS, PS and signaling. When a cell is at the center of carrier frequency coverage, the Ec/No measured value is used as the decision criterion of 2D and 2F. Set the event 2D threshold to a greater value if the compressed mode is expected to start as early as possible; otherwise set it to a lower value. To eliminate ping-pong start/stop of the compressed mode, increase appropriately the difference between the 2D and 2F thresholds.
Relevant Commands For parameters oriented to RNC inter-RAT handover algorithm: set them through SET INTERRATHOCOV, and query them through LST INTERRATHOCOV. For parameter oriented to cell inter-RAT handover algorithm: add them through ADD CELLINTERRATHOCOV, query them through LST CELLINTERRATHOCOV, and modify them through MOD CELLINTERRATHOCOV.
2.3.9 Inter-RAT Handover Judging Thresholds Inter-RAT handover judging thresholds involve the inter-RAT CS service handover judging threshold InterRATCovHOCSThd and the inter-RAT PS service handover judging threshold InterRATCovHOPSThd.
Parameter ID InterRATCovHOCSThd InterRATCovHOPSThd
Value Range 0 to 63
Physical Value Range -110 dBmto -48 dBm 2-46
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(0 corresponds to the value lower than -110 dBm; 1 corresponds to -110 dBm; 2 corresponds to -109 dBm; ...; 63 corresponds to -48 dBm)
Parameter Setting The default values are 16, namely, -95 dBm. This set of parameters are used for inter-RAT coverage handover evaluation at the RNC side, that is, Tother_RATin the formula introduced below. It is the absolute threshold of inter-RAT cell quality (RSSI) at the time of inter-RAT handover judging. If the inter-RATquality in the inter-RAT measurement report obtained at a moment satisfies the following condition: Mother_RAT + CIO ≥ Tother_RAT + H/2 Then start the delay trigger timer Trigger-Timer, and handover judgment is made after the timer expires. If the inter-RAT quality satisfies the following condition before the timer gets expired: Mother_RAT + CIO < Tother_RAT - H/2 Then the timer stops timing, and the RNC goes on waiting for receiving of the inter-RAT measurement report.
Impact on the Network Performance Configure these parameters differently according to different policies. If the MS can be handed over only after the GSM cell quality is good enough, this parameter can be increased properly, -85 dBm for example.
Relevant Commands For parameters oriented to RNC inter-RAT handover algorithm: set them through SET INTERRATHOCOV, and query them through LST INTERRATHOCOV. For parameter oriented to cell inter-RAT handover algorithm: add them through ADD CELLINTERRATHOCOV, query them through LST CELLINTERRATHOCOV, and modify them through MOD CELLINTERRATHOCOV.
2.3.10 Time to Trigger Related to Inter-RAT Handover In coverage-oriented inter frequency handover, the time-to-trigger parameters include time-totrigger for 2D (TrigTime2D), time-to-trigger for 2F (TrigTime2F) and time-to-trigger for 3A (TrigTime3A).
Parameter ID TrigTime2D TrigTime2F TrigTime3A
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Value Range Enum (D0,D10,D20,D40,D60,D80,D100,D120,D160,D200,D240,D320,D640,D1280,D2560,D5000 ), working range: Enum(D0, D200, D240, D640, D1280, D2560, D5000)
Physical Value Range Enum (0, 10, 20, 40, 60, 80, 100, 120, 160, 200, 240, 320, 640, 1280, 2560, 5000) ms Physical value range of TrigTimeHHO is 0 to 64,000 ms
Parameter Setting The default values are TrigTime3A: D0; TrigTime2D: D320; and TrigTime2F: D1280.
Impact on the Network Performance The greater the time-to-trigger values are, the smaller the average handover frequency is; but the increase of the time-to-trigger setting increases the risk of call drop.
Relevant Commands Parameters oriented to RNC inter-RAT handover algorithm: set them through SET INTERRATHOCOV, and query them through LST INTERRATHOCOV. Parameters oriented to cell inter-RAT handover algorithm: add them through ADD CELLINTERRATHOCOV, query them through LST CELLINTERRATHOCOV, and modify them through MOD CELLINTERRATHOCOV.
2.3.11 Hysteresis Related to Coverage-Based Inter-RAT Handover In the coverage-based inter-RAT handover, hystereses triggered by events include 3A hysteresis Hystfor3A, 2D hysteresis Hystfor2D, 2F hysteresis Hystfor2F, and inter-RAT handover hysteresis HystforInterRAT.
Parameter ID Hystfor3A Hystfor2D Hystfor2F HystforInterRAT
Value Range Hystfor2D and Hystfor2F: 0 to 29 Hystfor3A and HystforInterRAT: 0 to 15
Physical Value Range Hystfor2D and Hystfor2F: 0 dB to 14.5 dB, step 0.5 dB 2-48
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Hystfor3A and HystforInterRAT: 0 dB to 7.5 dB, step 0.5 dB
Parameter Setting The default values for Hystfor2D , Hystfor2F and Hystfor3A are 4 (2dB). The default value for HystforInterRAT is 0 (0 dB). Here, HystforInterRAT is used to prevent wrong judgment caused by abrupt signal jitter during inter-RAT handover judging, and it, together with the inter-RAT quality threshold, determines whether to trigger an inter-RAT handover judgment.
Impact on the Network Performance The greater the hystereses values, the stronger the capability for resisting signal fluctuation, and the ping-pong effect is suppressed, but the response speed to signal change by the handover algorithm is weakened. If the inter-RAT handover hysteresis is set too high, the requirement for inter-RAT quality is high, it is hard to trigger inter-RAT handover judging condition, and the call drop ratio increases.
Relevant Commands For parameters oriented to RNC inter-RAT handover algorithm: set them through SET INTERRATHOCOV, and query them through LST INTERRATHOCOV. For parameters oriented to cell inter-RAT handover algorithm: add them through ADD CELLINTERRATHOCOV, query them through LST CELLINTERRATHOCOV, and modify them through MOD CELLINTERRATHOCOV.
2.3.12 Time to Trigger for Verified GSM Cell This parameter refers to the delay trigger time of GSM cell verified already by the BS identity code BSIC. If the signal quality of GSM neighboring cell always satisfies the inter-RAT handover judging condition in the time range stipulated by this parameter value, and the GSM neighboring cell is in the verified state, the network starts the inter-RAT handover process.
Parameter ID TimeToTrigForVerify
Value Range 0 to 64000
Physical Value Range 0 to 64000 ms
Parameter Setting The default value is 0, namely, handover immediately. Refer to the descriptions in the section about handover threshold. The trigger condition for interRAT handover judging: Mother_RAT + CIO ≥ Tother_RAT + H/2 Issue 01 (2007-08-30)
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If inter-RAT quality satisfies the above trigger condition, then start the delay trigger timer Trigger-Timer, and inter-RAT handover judgment can be made after the timer gets expired. The length of this delay trigger timer is called delay trigger time. This parameter, together with hysteresis, is used to prevent wrong judgment caused by signal jitter during inter-RAT handover judging.
Impact on the Network Performance The longer the delay trigger time, the more difficult the handover occurs. The increase of the delay trigger time increases the call drop risk.
Relevant Commands For parameter oriented to RNC inter-RAT handover algorithm: set it through SET INTERRATHOCOV, and query it through LST INTERRATHOCOV. For parameter oriented to cell inter-RAT handover algorithm: add it through ADD CELLINTERRATHOCOV, query it through LST CELLINTERRATHOCOV, and modify it through MOD CELLINTERRATHOCOV.
2.3.13 Time to Trigger for Non-verified GSM Cell This parameter represents the delay time for triggering a GSM cell unacknowledged by BSIC. In the period specified by this parameter, if the signal quality of an adjacent GSM cell meets the requirement for inter-RAT handover and this cell is unacknowledged, the network starts interRAT handover.
Parameter ID TimeToTrigForNonVerify
Value Range 0 to 64000, 65535
Physical Value Range 0 to 64000 ms, the value 65535 means that the RNC does not hand over to an unacknowledged GSM cell
Parameter Setting The default value is 65535, namely, the RNC does not hand over to an unacknowledged GSM cell.
Impact on the Network Performance The longer the trigger is delayed , the more difficult the handover occurs. The increase of the delay trigger time increases the call dropping risk.
Relevant Commands For parameter oriented to RNC inter-RAT handover algorithm: set it through SET INTERRATHOCOV, and query it through LST INTERRATHOCOV. 2-50
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For parameter oriented to cell inter-RAT handover algorithm: add it through ADD CELLINTERRATHOCOV, query it through LST CELLINTERRATHOCOV, and modify it through MOD CELLINTERRATHOCOV.
2.3.14 Penalty Time for Inter-RAT Handover For inter-RAT handover failure to the GSM cell, possibly it is refused because the load of this cell is heavy. Therefore, no inter-RAT handover request is sent to this cell in the time range stipulated by this parameter value.
Parameter ID PenaltyTimeforInterRATHO
Value Range 0 to 60
Physical Value Range 0 to 60 s
Parameter Setting The default value is 30 s.
Impact on the Network Performance The penalty time may be too short because the load status of the GSM cell is not changed, and handover fails again. However, increase of the penalty trigger time increases the call dropping risk.
Relevant Commands For parameter oriented to RNC inter-RAT handover algorithm: set it through SET INTERRATHOCOV, and query it through LST INTERRATHOCOV. For parameter oriented to cell inter-RAT handover algorithm: add it through ADD CELLINTERRATHOCOV, query it through LST CELLINTERRATHOCOV, and modify it through MOD CELLINTERRATHOCOV.
2.3.15 Cell Individual Offset This parameter refers to the inter-RAT handover cell individual offset.
Parameter ID CellIndividalOffset
Value Range -50 to 50 Issue 01 (2007-08-30)
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Physical Value Range -50 dB to 50 dB
Parameter Setting The default value is 0 dB. This parameter is used for the inter-RAT handover judging process. Set it based on the landform feature of the GSM cell. UE uses the original measurement value of this cell plus this offset as the measurement result for UE handover judging. It functions as the mobile cell border in the handover algorithm. The greater the parameter, the higher the handover priority of this GSM cell. Generally, configure it to 0 dB.
Impact on the Network Performance The greater this parameter, the easier to hand over to the GSM, and vice versa.
Relevant Commands Set it through ADD GSMNCELL, query it through LST GSMNCELL, and modify it through MOD GSMNCELL.
2.3.16 Current Used Frequency Quality Threshold of Inter-RAT Handover This parameter is used for measurement control of event 3A when the event reporting mode is adopted for the inter-RAT measurement. Only when the quality of used frequency is poorer than this threshold, one of the mandatory conditions for triggering event 3A is satisfied.
Parameter ID Based on different inter-RAT measurement quantities in use and different borne services, this parameter can be categorized as follows: l
IRHOUsedFreqCSThdEcN0 (used frequency Ec/No quality threshold of CS service)
l
IRHOUsedFreqPSThdEcN0 (used frequency Ec/No quality threshold of PS service)
l
IRHOUsedFreqCSThdRSCP (used frequency RSCP quality threshold of CS service)
l
IRHOUsedFreqPSThdRSCP (used frequency RSCP quality threshold of PS service)
Value Range IRHOUsedFreqCSThdEcN0 and IRHOUsedFreqPSThdEcN0: -24 to 0 IRHOUsedFreqCSThdRSCP and IRHOUsedFreqPSThdRSCP: -115 to -25
Physical Value Range IRHOUsedFreqCSThdEcN0 and IRHOUsedFreqPSThdEcN0: -24 dB to 0 dB IRHOUsedFreqCSThdRSCP and IRHOUsedFreqPSThdRSCP: -115 dBm to -25 dBm 2-52
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Parameter Setting The default values for each parameter are as follows: l
IRHOUsedFreqCsThdEcN0: -12 dB
l
IRHOUsedFreqPsThdEcN0: -13 dB
l
IRHOUsedFreqCsThdRscp: -97 dB
l
IRHOUsedFreqPsThdRscp: -107 dB
Factors to be considered while setting these parameters: Only when the quality of the current used frequency satisfies QUsed ≤ TUsed - H3a/2 and the quality of target frequency satisfies Mother_RAT + CIO ≥ Tother_RAT + H/2, delay the time for triggering the timer when the event reporting mode is adopted for inter-RAT measurement. A 3A event is report upon expiry of the timer. where, l
QUsed: estimated quality of the UTRAN frequency currently used.
l
Tused: indicates the quality threshold for the inter-RAT frequency currently used.
l
Mother_RAT: indicates the inter-RAT (GSM RSSI) measurement results.
l
Tother_RAT: indicates the threshold for judging the inter-RAT handover.
l
Cell individual offset (CIO): indicates the offset set by inter-RAT cells.
l
H: indicates the hysteresis. The setting on the hysteresis reduces incorrect judgement caused by jitter signals.
When the cell signal quality of current frequency is poor and is lower than the threshold defined by this parameter, infer that the current frequency cannot better satisfy the coverage requirement of current service. The event 2F indicates that the current frequency quality is restored. Therefore, this parameter should be set less than the trigger threshold of event 2F or equal to the threshold of event 2D. For composite services, use the parameters configured for CS services.
Impact on the Network Performance Higher values of these parameters get event 3A to be more easily triggered. When the value of this parameter is too high, the UE may perform handover even when the signal quality is good in current system.
Relevant Commands Parameter oriented to RNC inter-RAT handover algorithm: set it through SET INTERRATHOCOV and query it through LST INTERRATHOCOV. Parameter oriented to the cell inter-RAT handover algorithm, add it through ADD CELLINTERRATHOCOV, query it through LST CELLINTERRATHOCOV, and modify it through MOD CELLINTERRATHOCOV.
2.3.17 Inter-RAT Measure Timer Length This parameter defines the valid time for inter-RAT measurement. If the timer cannot find an appropriate inter-RAT cell to initiate the inter-RAT handover, for instance, the event 3A report is not received or all period reports cannot satisfy the trigger condition for the inter-RAT Issue 01 (2007-08-30)
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handover, the RNC disables the compress mode to release the resources for inter-RAT measurement and waits for the inter-RAT measurement of the next round.
Parameter ID InterRATMeasTime
Value Range 0 to 512
Physical Value Range 0 means that the system does not start the inter-RAT measurement timer. 1 s to 512 s.
Parameter Setting The default value is 60 s. Factors to be considered while setting these parameters: This parameter is used to prevent the UE from being in compress mode for a long time when the UE stands still or moves slowly. The UE's being in compress mode not only disrupts the service quality, but brings extra interference into the system and decreases the system capability. Most of the inter-RAT handover can be complete within 60 seconds.
Impact on the Network Performance If this parameter is set too small, the UE cannot perform the inter-RAT handover. If this parameter is set too great, the UE performs the inter-RAT handover too frequently. In the actual network, you can collect the statistics on the inter-RAT handover and adopt an appropriate value at the convenience of most users.
Relevant Commands Parameter oriented to RNC inter-RAT handover algorithm: set it through SET INTERRATHOCOV and query it through LST INTERRATHOCOV. Parameter oriented to the cell inter-RAT handover algorithm, add it through ADD CELLINTERRATHOCOV, query it through LST CELLINTERRATHOCOV, and modify it through MOD CELLINTERRATHOCOV.
2.4 Non Coverage-Based Inter-RAT Handover Management Parameters The common configurable non-coverage-based inter-RAT handover management parameters are listed here.
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Table 2-4 List of non-coverage-based inter-RAT handover management parameters No.
Parameter ID
Parameter Meaning
Defaul t Value
Relevant Command
Level
1
CSServiceHOSw itch
Inter-RAT service handover switch
OFF
Set: ADD CELLHOCOM M
CELL
PSServiceHOSw itch
Query: LST CELLHOCOM M Modify: MOD CELLHOCOM M
2
InterRATFilterC oef
Inter-RAT measurement filter coefficient
D3
3
Hystfor3C
Hysteresis of event 3C
0 dB
4
TrigTime3C
Time-to-Trigger for event 3C
D640 (640 ms)
5
BSICVerify
BSIC verify selection switch
Require d
6
InterRATNCovH OCSThd
Non-CoverageBased inter-RAT handover judging thresholds
21, that is, -90 dBm
InterRATNCovH OPSThd 7
PenaltyTimeforI nterRATHO
Penalty Time for inter-RAT handover
30 s
8
InterRATHOAtte mpts
Inter-RAT handover max attempt times
16 times
9
InterRATMeasTi me
Inter-RAT measure timer length
60 s
For RNC Set or modify: SET INTERRATH ONCOV Query: LST INTERRATH ONCOV For Cell Set: ADD CELLINTERR ATHONCOV Query: LST CELLINTERR ATHONCOV Modify: MOD CELLINTERR ATHONCOV
RNC Cell
2.4.1 Inter-RAT Service Handover Switches These parameters decide whether the cell allows triggering CS and PS service handover. 2.4.2 Inter-RAT Measurement L3 Filter Coefficient This parameter refers to the measurement smooth coefficient adopted for L3 inter-RAT measurement report filter in the inter-RAT handover based on non-coverage. 2.4.3 Hysteresis of Event 3C This parameter refers to the trigger hysteresis of event 3C of inter-RAT handover based on noncoverage. Issue 01 (2007-08-30)
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2.4.4 Time to Trigger for Event 3C This parameter refers to the delay trigger event of event 3C of inter-RAT handover based on non-coverage. 2.4.5 BSIC Verify Selection Switch This parameter is used to control the inter-RAT measurement report cell in the inter-RAT handover based on non-coverage. 2.4.6 Non Coverage-Based Inter-RAT Handover Judging Thresholds Inter-RAT handover judging thresholds based on non-coverage involve the non-coverage interRAT CS service handover judging threshold InterRATNCovHOCSThd and the non-coverage inter-RAT PS service handover judging threshold InterRATNCovHOPSThd. 2.4.7 Penalty Time for Inter-RAT Handover This parameter refers to the penalty timer adopted when the non-coverage-based inter-RAT handover fails. This parameter is valid for both service and load handover. 2.4.8 Inter-RAT Handover Max Attempt Times This parameter is the maximum attempts of none-coverage-based inter-RAT handover. 2.4.9 Inter-RAT Measure Timer Length This parameter defines that the system will stop inter-RAT measurement and disables the compressed mode if enabled if no inter-RAT handover occurs upon expiry of the inter-RAT measurement timer.
2.4.1 Inter-RAT Service Handover Switches These parameters decide whether the cell allows triggering CS and PS service handover.
Parameter ID CSServiceHOSwitch PSServiceHOSwitch
Value Range Enum (ON, OFF)
Physical Value Range None.
Parameter Setting The default values are OFF. The service handover refers to the service handover attribute of each service and configuration of related parameters at network side. Once the service is set up, the related measurement is immediately triggered and inter-RAT handover is performed. The two switches are just ON only when the service handover function is necessary. Normally they are OFF.
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Impact on the Network Performance Set the two switches according to the actual network handover strategies.
Relevant Commands For cell-oriented common handover parameters: add them through ADD CELLHOCOMM, query them through LST CELLHOCOMM, and modify them through MOD CELLHOCOMM.
2.4.2 Inter-RAT Measurement L3 Filter Coefficient This parameter refers to the measurement smooth coefficient adopted for L3 inter-RAT measurement report filter in the inter-RAT handover based on non-coverage.
Parameter ID InterRATFilterCoef
Value Range Enum (D0, D1, D2, D3, D4, D5, D6, D7, D8, D9, D11, D13, D15, D17, D19)
Physical Value Range Enum (0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 15, 17, 19)
Parameter Setting The default values is D3, namely 3. The physical meaning and measurement model of this parameter are the same as those of the inter-RAT handover measurement filter coefficient based on coverage. For the detailed analysis, refer to 2.3.1 Inter-RAT Measurement L3 Filter Coefficients.
Impact on the Network Performance The greater this parameter, the stronger the effect on signal smoothness, the stronger the fastfading resistance capability, but the weaker the tracing capability for signal change, and call drops due to handover failure. If this value is set too low, unnecessary system handover occurs.
Relevant Commands For parameter oriented to the RNC non-coverage inter-RAT handover algorithm: set it through SET INTERRATHONCOV, and query it through LST INTERRATHONCOV. For parameter oriented to cell non-coverage inter-RAT handover algorithm: add it through ADD CELLINTERFREQHONCOV, query it through LST CELLINTERFREQHONCOV, and modify it through MOD CELLINTERFREQHONCOV.
2.4.3 Hysteresis of Event 3C This parameter refers to the trigger hysteresis of event 3C of inter-RAT handover based on noncoverage. Issue 01 (2007-08-30)
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Parameter ID Hystfor3C
Value Range 0 to 15
Physical Value Range 0 dB to 7.5 dB, step 0.5 dB
Parameter Setting The default value for Hystfor3C is 0 (0 dB). Event 3C means the GSM cell quality is greater than an absolute threshold. Event 3C is used for inter-RAT load handover and service handover. When the inter-RAT cell satisfies the following condition, event 3C report is triggered, and the corresponding cell is placed in the event 3C trigger list. Report of event 3C is not repeated for the cell in the list. MotherRAT + CIOotherRAT ≥ TotherRAT + H3C/2 Here, l
H3C is event 3C hysteresis, namely, the parameter Hystfor3C.
l
TotherRAT is the report threshold of inter-RAT cell trigger event, and the corresponding parameter is based on non-coverage inter-RAT handover threshold.
When the cell in the list satisfies the following condition: MotherRAT + CIOotherRAT ≤ TotherRAT - H3C/2 The corresponding cell is deleted from the list.
Impact on the Network Performance The greater the hysteresis, the stronger the capability for resisting signal fluctuation, and the ping-pong effect is suppressed, but the response speed to signal change by the handover algorithm is weakened. If the inter-RAT handover hysteresis is set too high, the requirement for inter-RAT quality is high, it is hard to trigger inter-RAT handover judging condition, and the call dropping ratio increases.
Relevant Commands For parameter oriented to the RNC non-coverage inter-RAT handover algorithm: set it through SET INTERRATHONCOV, and query it through LST INTERRATHONCOV. For parameter oriented to cell non-coverage inter-RAT handover algorithm: add it through ADD CELLINTERFREQHONCOV, query it through LST CELLINTERFREQHONCOV, and modify it through MOD CELLINTERFREQHONCOV. 2-58
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2.4.4 Time to Trigger for Event 3C This parameter refers to the delay trigger event of event 3C of inter-RAT handover based on non-coverage.
Parameter ID TrigTime3C
Value Range Enum (D0, D10, D20, D40, D60, D80, D100, D120, D160, D200, D240, D320, D640, D1280, D2560, D5000)
Physical Value Range Enum (0, 10, 20, 40, 60, 80, 100, 120, 160, 200, 240, 320, 640, 1280, 2560, 5000) ms
Parameter Setting The default value is D640, that is 640 ms. The delay trigger time aims to reduce excessive events reports triggered occasionally for a measurement result. Considering that the period for reporting to its L3 by the physical layer of inter-RAT measurement UE is 480 ms, set it as the default value here temporarily.
Impact on the Network Performance The longer the delay is triggered, the more difficult the handover occurs, but increase of the delay trigger time increases the call dropping risk.
Relevant Commands For parameter oriented to the RNC non-coverage inter-RAT handover algorithm: set it through SET INTERRATHONCOV, and query it through LST INTERRATHONCOV. For parameter oriented to cell non-coverage inter-RAT handover algorithm: add it through ADD CELLINTERFREQHONCOV, query it through LST CELLINTERFREQHONCOV, and modify it through MOD CELLINTERFREQHONCOV.
2.4.5 BSIC Verify Selection Switch This parameter is used to control the inter-RAT measurement report cell in the inter-RAT handover based on non-coverage.
Parameter ID BSICVerify
Value Range Enum (Require, Not_Require) Issue 01 (2007-08-30)
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Physical Value Range None.
Parameter Setting The default value is Require. If it is set as required, report is allowed only after the measured GSM cell identity code (BSIC) is correctly decoded. If it is set to Non_Require, all the measured cells can be reported so long as they satisfy the previous report condition, regardless of their BSICs whether correctly decoded or not. Usually, the handover due to non-coverage has a lower requirement for handover timeliness, but has a higher requirement for the handover success rate. It is recommended to always set it to Require to ensure the handover reliability.
Impact on the Network Performance When it is set to Not_Require, the handover occurs easily, but the handover is not as reliable as the Require mode.
Relevant Commands Parameter oriented to the RNC non-coverage inter-RAT handover algorithm: set it through SET INTERRATHONCOV, and it query through LST INTERRATHONCOV. Parameter oriented to cell non-coverage inter-RAT handover algorithm: add it through ADD CELLINTERRATHONCOV, query it through LST CELLINTERRATHONCOV, and modify it through MOD CELLINTERRATHONCOV.
2.4.6 Non Coverage-Based Inter-RAT Handover Judging Thresholds Inter-RAT handover judging thresholds based on non-coverage involve the non-coverage interRAT CS service handover judging threshold InterRATNCovHOCSThd and the non-coverage inter-RAT PS service handover judging threshold InterRATNCovHOPSThd.
Parameter ID InterRATNCovHOCSThd InterRATNCovHOPSThd
Value Range 0 to 63
Physical Value Range -110 dBm to -48 dBm (0 corresponds to the value lower than -110 dBm; 1 corresponds to -110 dBm; 2 correspondsto -109 dBm; ...; 63 corresponds to -48 dBm) 2-60
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Parameter Setting All the default values are 21, namely, -90 dBm. See the judging formula in 3C hysteresis.
Impact on the Network Performance Configure these parameters differently according to different policies. If the MS can be handed over only after the GSM cell quality is good enough, this parameter can be increased properly, -85 dBm for example.
Relevant Commands For parameter oriented to the RNC non-coverage inter-RAT handover algorithm: set it through SET INTERRATHONCOV, and query it through LST INTERRATHONCOV. For parameter oriented to cell non-coverage inter-RAT handover algorithm: add it through ADD CELLINTERFREQHONCOV, query it through LST CELLINTERFREQHONCOV, and modify it through MOD CELLINTERFREQHONCOV.
2.4.7 Penalty Time for Inter-RAT Handover This parameter refers to the penalty timer adopted when the non-coverage-based inter-RAT handover fails. This parameter is valid for both service and load handover.
Parameter ID PenaltyTimeForInterRATHO
Value Range 0 to 65535
Physical Value Range 0 to 65535 s
Parameter Setting The default value is 30 s. More devices take part in inter-RAT handover, the flow is complex, the delay is long, and the probability corresponding to intra-system handover failure may be high. In addition, it may be hard to recover the cause leading to failure in a short time. To reduce unnecessary handover retries for the same cell and effect on processing of other flows, the penalty timer is added to restrict multiple retries for the same cell in a short time. The specific value can be adjusted according to the actual requirement.
Impact on the Network Performance The penalty time may be too short because the load status of the GSM cell is not changed, and the handover fails again. However, increase of the penalty trigger time increases the call dropping risk. Issue 01 (2007-08-30)
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Relevant Commands For parameter oriented to the RNC non-coverage inter-RAT handover algorithm: set it through SET INTERRATHONCOV, and query it through LST INTERRATHONCOV. For parameter oriented to cell non-coverage inter-RAT handover algorithm: add it through ADD CELLINTERFREQHONCOV, query it through LST CELLINTERFREQHONCOV, and modify it through MOD CELLINTERFREQHONCOV.
2.4.8 Inter-RAT Handover Max Attempt Times This parameter is the maximum attempts of none-coverage-based inter-RAT handover.
Parameter ID InterRATHOAttempts
Value Range 0 to 16
Physical Value Range 0 to 16 times
Parameter Setting The default value is 16 times. Since more devices take part in the inter-RAT handover which has a complex flow, the handover may take a longer delay, and the probability that the handover fails is relatively higher. If the inter-RAT handover fails too much, the network resource is wasted and the service quality is not guaranteed. Such problems can be effectively controlled by setting this parameter.
Impact on the Network Performance l
The higher the parameter is, the higher the probability is of the UE handover from one system to another.
l
The lower the parameter is, the smaller influence is on the network quality.
Relevant Commands Parameter oriented to the RNC non-coverage inter-RAT handover algorithm: set it through SET INTERRATHONCOV, and query it through LST INTERRATHONCOV. Parameter oriented to cell non-coverage inter-RAT handover algorithm: add it through ADD CELLINTERRATHONCOV, query it through LST CELLINTERRATHONCOV, and modify it through MOD CELLINTERRATHONCOV.
2.4.9 Inter-RAT Measure Timer Length This parameter defines that the system will stop inter-RAT measurement and disables the compressed mode if enabled if no inter-RAT handover occurs upon expiry of the inter-RAT measurement timer. 2-62
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Parameter ID InterRATMeasTime
Value Range 0 to 512
Physical Value Range 0 means the system does not start the inter-RAT measurement timer 1 s to 512 s
Parameter Setting The default value is 60 s. To close compress mode in coverage-based inter-RAT handover can trigger event 2F, since there is not event 2F in non-coverage-based inter-RAT handover, it only depends on the measurement timer.
Impact on the Network Performance The higher the parameter value is, the bigger the probability of the UE handover from one system to another one is. However, the lower the parameter value is, the smaller the influence to network quality is.
Relevant Commands Parameter oriented to the RNC non-coverage inter-RAT handover algorithm: set it through SET INTERRATHONCOV, and query it through LST INTERRATHONCOV. Parameter oriented to cell non-coverage inter-RAT handover algorithm: add it through ADD CELLINTERRATHONCOV, query it through LST CELLINTERRATHONCOV, and modify it through MOD CELLINTERRATHONCOV.
2.5 Blind Handover Management Parameters The common configurable blind handover management parameters are listed here. Table 2-5 List of blind handover management parameters
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No.
Paramet er ID
Parameter Meaning
Default Value
Relevant Command
Level
1
BlindHoF lag
Blind handover flag
FALSE
For Inter-Freq Set: ADD INTERFREQNCE LL
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No.
Paramet er ID
Parameter Meaning
Default Value
Relevant Command
2
BlindHO Prio
Blind handover priority
-
Query: LST INTERFREQNCE LL Modify: MOD INTERFREQNCE LL For Inter-RAT Set:ADD GSMNCELL Query: LST GSMNCELL ModifyMOD GSMNCELL
Level
2.5.1 Blind Handover Flag This parameter indicates whether the blind handover is performed to the neighboring cell. Blind handover means UE can directly handover to the neighboring cell without measuring it. 2.5.2 Blind Handover Priority If the BlindHOFlag is TRUE, the BlindHOPrio is used to appoint the blind handover priority of the neighboring cell.
2.5.1 Blind Handover Flag This parameter indicates whether the blind handover is performed to the neighboring cell. Blind handover means UE can directly handover to the neighboring cell without measuring it.
Parameter ID BlindHoFlag
Value Range Enum (FALSE and TRUE)
Physical Value Range None.
Parameter Setting The default value of BlindHoFlag is FALSE. If there is a same coverage inter-freq neighboring cell, it can be set to TRUE.
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Impact on the Network Performance Set the parameter according to actual network handover strategies. It may affect KPI performance concerning the cells if the blind handover is allowed in related cells, especially the emergent blind handover is.
Relevant Commands For inter-frequency handover neighboring cell parameter: add it through ADD INTERFREQNCELL , query it through LST INTERFREQNCELL , and modify it through MOD INTERFREQNCELL. For inter-RAT handover neighboring cell parameter: add it through ADD GSMNCELL, query it through LST GSMNCELL, and modify it through MOD GSMNCELL.
2.5.2 Blind Handover Priority If the BlindHOFlag is TRUE, the BlindHOPrio is used to appoint the blind handover priority of the neighboring cell.
Parameter ID BlindHOPrio
Value Range BlindHOPrio: 0 to 30
Physical Value Range None.
Parameter Setting For this parameter, 0 represents the highest priority. The value range corresponds to only one cell. Priorities 0 to 15 are assigned to concentric neighboring cells, which can ensure successful handover. Priorities 16 to 30 are assigned to neighboring cells for blind handover, which cannot ensure successful handover.
Impact on the Network Performance Set the parameter according to actual network handover strategies.
Relevant Commands For inter-frequency handover neighboring cell parameter: add it through ADD INTERFREQNCELL , query it through LST INTERFREQNCELL , and modify it through MOD INTERFREQNCELL. For inter-RAT handover neighboring cell parameter: add it through ADD GSMNCELL, query it through LST GSMNCELL, and modify it through MOD GSMNCELL. Issue 01 (2007-08-30)
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2.6 Cell Selection and Reselection The common configurable cell selection and reselection parameters are listed here. Table 2-6 List of cell selection and reselection parameters No.
Parameter ID
Param eter Meani ng
Default Value
Relevant Command
Level
1
IdleQhyst1s
Measur ement hysteres is paramet ers
Qhyst1s: 2 (4 dB)
Set: ADD CELLSELRESEL
Cell
Qhyst2s: 1 (2 dB)
Modify: MOD CELLSELRESEL
Load level offsets
0 dB
For intra-reeq
IdleQhyst2s ConnQhyst1s ConnQhyst2s 2
IdleQoffset1sn IdleQoffset2sn ConnQoffset1s n
Query: LST CELLSELRESEL
Set: ADD INTRAFREQNCELL Query: LST INTRAFREQNCELL
ConnQoffset2s n
Modify:MOD INTRAFREQNCELL
Qoffset1sn
For inter-freq Set: ADD INTERFREQNCELL Query: LST INTERFREQNCELL Modify: MOD INTERFREQNCELL For inter_RAT Set: ADD GSMNCELL Query: LST GSMNCELL Modify: MOD GSMNCELL
3
4
2-66
Qqualmin
Qrxlevmin
Minimu m quality criterio n
-18 dB
Minimu m access level
-58, that is, -115 dBm
Set: ADD CELLSELRESEL Query: LST CELLSELRESEL Modify: MOD CELLSELRESEL
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No.
Parameter ID
Param eter Meani ng
Default Value
5
IdleSintrasearc h
Cell reselecti on start threshol ds
IdleSintra search and ConnSint rasearch: 5 (10 dB)
ConnSintrasear ch IdleSintersearc h
Relevant Command
Level
NCell
IdleSinter search and ConnSint ersearch: 4 (8 dB)
ConnSintersear ch SsearchRat
Ssearchra t: 2 (4 dB)
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Treselections
Reselec tion hysteres is time
1s
7
Qrxlevmin
Minimu -58, that m is, -115 access dBm level for interRAT cell
Set: ADD GSMNCELL
N/A
8
Qsearch_I
2G Idle mode MS's searchin g for 3G cell signal level threshol d
7, that is, always
9
FDD_Qoffset
3G cell reselecti on signal level offset
0 dB
Query: LST GSMNCELL Modify: MOD GSMNCELL
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No.
Parameter ID
Param eter Meani ng
Default Value
10
FDD_Qmin
3G cell reselecti on signal level threshol d
–10 dB
Relevant Command
Level
2.6.1 Measurement Hysteresis Parameters The measurement hysteresis parameters include measurement hysteresis 1 (Qhyst1s) and measurement hysteresis 2 (Qhyst2s), which are used for the UE to measure the service cell CPICH RSCP (Qhyst1s) and CPICH Ec/No (Qhyst2s) respectively . IdleQhyst1s and IdleQhyst2s are used in idle state, ConnQhyst1s and ConnQhyst2s are used in connecting state. 2.6.2 Load Level Offsets These parameters are cell offsets used for cell selection and reselection. In the cell selection / reselection process, when CPICH Ec/N0 is used for measurement, the cell offset is QOffset2sn; when CPICH RSCP is used for measurement, IdleQoffsets and IdleQoffset2s used to idle state, ConnQoffset1s and ConnQoffset2s used to connecting state. There exist ConnQoffset1s and ConnQoffset2s only if SIB12 indication is set TRUE. In addition, there is only QOffset1sn in inter-RAT cell selection and reselection, namely, not idle, connect, or QOffset2sn. 2.6.3 Minimum Quality Criterion This parameter is the minimum access threshold of PCPICH Ec/N0. The UE can reside in the cell only when CPICH Ec/N0 measured by the UE is bigger than this threshold. 2.6.4 Minimum Access Level This parameter is the minimum access level threshold of PCPICH RSCP. The UE can reside in this cell only when CPICH RSCP measured by the UE is greater than this threshold. 2.6.5 Cell Reselection Start Thresholds These parameters include the intra-frequency cell reselection start threshold (Including Idle and connecting state), the inter-frequency cell reselection start threshold (Including Idle and connecting state) and the inter-RAT cell reselection start threshold (SsearchRat). 2.6.6 Reselection Hysteresis Time If the signal quality of other cells (CPICH Ec/No measured by the UE) is always better than the quality of the current cell within the time specified by this parameter, the UE will reselect this cell to reside in. 2.6.7 Minimum Access Level for Inter-RAT Cell This parameter is the minimum access level threshold of inter-RAT cell. The UE can reside in this cell only when GSM RSSI measured by the UE is greater than this threshold. 2.6.8 2G Idle Mode MS's Searching for 3G Cell Signal Level Threshold A GSM MS in idle mode starts to search for 3G signal level threshold. 2.6.9 3G Cell Reselection Signal Level Offset A 3G cell can be reselected when the average signal level of the target 3G cell is FDD_Qosffset greater than that of the current serving cell. 2-68
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2.6.10 3G Cell Reselection Signal Level Threshold Only when the signal level in the target 3G cell is FDD_Qmin greater than the serving cell, the target 3G cell may become a candidate cell for reselection.
2.6.1 Measurement Hysteresis Parameters The measurement hysteresis parameters include measurement hysteresis 1 (Qhyst1s) and measurement hysteresis 2 (Qhyst2s), which are used for the UE to measure the service cell CPICH RSCP (Qhyst1s) and CPICH Ec/No (Qhyst2s) respectively . IdleQhyst1s and IdleQhyst2s are used in idle state, ConnQhyst1s and ConnQhyst2s are used in connecting state.
Parameter ID IdleQhyst1s IdleQhyst2s ConnQhyst1s ConnQhyst2s
Value Range 0 to 20
Physical Value Range 0 dB to 40 dB, step 2 dB
Parameter Setting The default value of Qhyst1s is 2 (4 dB), and the default value of Qhyst2s is 1 (2 dB). Qhyst2s is optional. If it is not configured, Qhyst2s has the same value of measurement hysteresis 1. According to the R criterion, the measured value of the current service cell participates in cell reselection sequencing after this hysteresis is added to it. The values of these parameters are related to the slow fading property of the area where the cell is located. These parameters are used mainly to prevent the ping-pong effect of the cell reselection result due to the slow fading when the UE is at the cell verge. The ping-pong effect may cause frequent location updates (idle mode), URA updates (URA_PCH) or cell updates (CELL_FACH, CELL_PCH); which results in increased network signaling load and higher loss of UE battery energy.
Impact on the Network Performance The greater these hysteresis parameters, the less likely the various types of cell reselections occur, and the better the slow fading resistance capability, but the slower the reaction to the environment changes.
Relevant Commands Set these parameters through ADD CELLSELRESEL, query them through LST CELLSELRESEL, and modify them through MOD CELLSELRESEL. Issue 01 (2007-08-30)
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2.6.2 Load Level Offsets These parameters are cell offsets used for cell selection and reselection. In the cell selection / reselection process, when CPICH Ec/N0 is used for measurement, the cell offset is QOffset2sn; when CPICH RSCP is used for measurement, IdleQoffsets and IdleQoffset2s used to idle state, ConnQoffset1s and ConnQoffset2s used to connecting state. There exist ConnQoffset1s and ConnQoffset2s only if SIB12 indication is set TRUE. In addition, there is only QOffset1sn in inter-RAT cell selection and reselection, namely, not idle, connect, or QOffset2sn.
Parameter ID IdleQoffset1sn IdleQoffset2sn ConnQoffset1sn ConnQoffset2sn Qoffset1sn
Value Range -50 to 50
Physical Value Range -50 dB to 50 dB, step 1 dB
Parameter Setting The default values are 0 dB. These parameters are offsets of CPICH measured values of neighboring cells. QOffset1sn is used for the RSCP measurement and the neighboring cell measurement value participates in cell reselection sequencing after this offset is deducted from it. QOffset2sn is used for the Ec/No measurement and the neighboring cell measurement value participates in cell reselection sequencing after this offset is deducted from it. These parameters play the role of moving the cell boarder in the cell selection and reselection algorithms. They are configured according to the actual environment in network planning.
Impact on the Network Performance l
The greater these values, the lower the probability of selecting the neighboring cell.
l
The less these values are, the higher the probability of selecting the neighboring cell.
Relevant Commands For intra-frequency cell selection/reselection: set these parameters through ADD INTRAFREQNCELL, query them through LST INTRAFREQNCELL , and modify them through MOD INTRAFREQNCELL . For inter-frequency cell selection/reselection: set these parameters through ADD INTERFREQNCELL, query them through LST INTERFREQNCELL, and modify them through MOD INTERFREQNCELL. 2-70
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For inter-RAT cell selection and reselection: set these parameters through ADD GSMNCELL, query them through LST GSMNCELL, and modify them through MOD GSMNCELL.
2.6.3 Minimum Quality Criterion This parameter is the minimum access threshold of PCPICH Ec/N0. The UE can reside in the cell only when CPICH Ec/N0 measured by the UE is bigger than this threshold.
Parameter ID Qqualmin
Value Range -24 to 0
Physical Value Range -24 dB to 0 dB, step 1 dB
Parameter Setting The default value is -18 dB. The FDD mode is defined by the S criterion for cell selection in Protocol 25.304, as follows: Srxlev>0 & Squal>0 Where, l
Squal = Qqualmeas - Qqualmin
l
Srxlev = Qrxlevmeas - Qrxlevmin - Pcompensation
l
Qqualmeas is Ec/No of the measured value CPICH of the cell quality;
l
Qrxlevmeas is RSCP of CPICH;
l
Qrxlevmin is the minimum pilot signal receiving power required for the current cell;
l
Pcompensation = Max.(UE_TXPWR_MAX_RACH - P_MAX, 0); –
UE_TXPWR_MAX_RACH is the maximum allowed uplink transmit power of the UE when accessing to the cell, namely MaxAllowedULTxPower;
–
P_MAX is the maximum radio frequency output power of the UE.
Impact on the Network Performance The greater this parameter, the more difficult the UE selects this cell to reside in; the lower this parameter, the easier the UE selects this cell to reside in. However, if this parameter is too low, the UE fails to correctly receive the system information borne over PCCPCH after it resides in the cell.
Relevant Commands Set this parameter through ADD CELLSELRESEL, query it through LST CELLSELRESEL, and modify it through MOD CELLSELRESEL. Issue 01 (2007-08-30)
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2.6.4 Minimum Access Level This parameter is the minimum access level threshold of PCPICH RSCP. The UE can reside in this cell only when CPICH RSCP measured by the UE is greater than this threshold.
Parameter ID Qrxlevmin
Value Range -58 to -13
Physical Value Range -115 dBm to -25 dBm, step 2 dBm Where, -58 corresponds to -115 dBm, -57 corresponds to -113dBm,…, -13 corresponds to 25 dBm
Parameter Setting The default value is -58, namely -115 dBm. For the definition of Qrxlevmin, refer to Minimum Quality Criterion (Qqualmin). The settings of Qrxlevmin and Qqualmin should be considered together.
Impact on the Network Performance The greater this parameter, the more difficult the UE selects this cell to reside in; the lower this parameter, the easier the UE selects this cell to reside in. However, if this parameter is too low, the UE fails to receive the system information borne over PCCPCH correctly after it resides in this cell.
Relevant Commands Set this parameter through ADD CELLSELRESEL, query it through LST CELLSELRESEL, and modify it through MOD CELLSELRESEL.
2.6.5 Cell Reselection Start Thresholds These parameters include the intra-frequency cell reselection start threshold (Including Idle and connecting state), the inter-frequency cell reselection start threshold (Including Idle and connecting state) and the inter-RAT cell reselection start threshold (SsearchRat).
Parameter ID IdleSintrasearch IdleSintersearch ConnSintrasearch ConnSintersearch 2-72
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SsearchRat
Value Range -16 to 10
Physical Value Range -32 dB to 20 dB, step 2 dB
Parameter Setting The default values of IdleSintrasearch and ConnSintrasearch are 5 (10 dB), the default values of IdleSintersearch and ConnSintersearch are 4 (8 dB), and the default value of Ssearchrat is 2 (4 dB). The cell reselection start thresholds are defined in Protocol 25.304 as follows: 1.
If Sx
