3 wcdma handover
TRANSCRIPT
WCDMA Handover Principle and Relevant Parameterswww.huawei.com
Copyright 2006 Huawei Technologies Co., Ltd. All rights reserved.
Foreword
Why mobile systems need handover?It is decided by the characters of mobile system:
The mobility of UE The mobile system is composed by cells which the coverage ability is limited.
Providing the continuous service in mobile system is the basic element in QoS.
Copyright 2006 Huawei Technologies Co., Ltd. All rights reserved.
Page1
Objectives
Upon completion of this course, you will be able to:Know the basic definitions of Handover The algorithms of handover decision The handover flow The parameters of handover
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Page2
Contents1. Introduction of Handover 2. Measurement of Handover 3. The Basic Handovers
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Page3
Contents1. Introduction of Handover 2. Measurement of Handover 3. The Basic Handovers
Copyright 2006 Huawei Technologies Co., Ltd. All rights reserved.
Page4
The Purpose of Handover
Providing the continuous service in mobile system is the basic element in QoS
The load balance: sharing the resource The hierarchy divided by speed and service: high efficiency of using resource
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Page5
The Basic Concepts of Handover
Active Set Monitored Set Detected set Radio Link (RL) Radio Link Set (RLS)
maximum ratio combination selection combination The soft handover gain CPICH
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Page6
The Categories of Handover
According to the signaling characters
Soft handover (softer handover) Hard handover
According to the properties of source cell and target cell:
Intra-frequency handover Inter-frequency handover Inter-RAT handover (UMTS GSM/GPRS)
According to the purpose of handover:
Based on Coverage Based on Noncoverage
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Page7
The Characters of Different Handover
Comparison between soft handover and hard handover:
ItemThe number of RLs in active set after handover Interruption during handover The frequencies of cells
Soft HandoverSeveral One
Hard Handover
No
Yes
Only happened between Intrafrequency cells
Can be happened in Intrafrequency cells or Inter-frequency cells
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Page8
The Characters of Different Handover
Comparison between soft handover and softer handover :
ItemUL combination
Soft HandoverSignal combined in RNC by selective combination
Softer HandoverSignal combined in NodeB by maximum ratio combination
DL combination
Signal combined in UE by maximum ratio combination
Signal combined in UE by maximum ratio combination
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Page9
Soft HandoverRNC
NodeB 1
NodeB 2
Cell A
Cell B
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Page10
Softer HandoverRNC
NodeB
Cell A Cell B
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Page11
Hard HandoverRNC
NodeB 1
NodeB 2
Cell A
Cell B
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Page12
Three Steps of HandoverThe following figure shows handover procedure (measurement quality set to PCPICH Ec/No)Measure the CPICH Ec/N0 of the serving cell and its neighboring cells as well as the relative time difference between the cells
Measurement phase
Measurement
Decision
No Are handover criteria satisfied? Decision phase
Execution
Yes
Perform a handover and update relative parameters
Execution phase
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Page13
Contents1. Introduction of Handover 2. Measurement of Handover 3. The Basic Handovers
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Page14
Contents2. Measurement of Handover2.1 Measurement Control and Measurement Report 2.2 Measurement Phase
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Page15
Measurement Control
UE
UTRAN
MEASUREMENT CONTROL
Measurement Control, normal case
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Page16
Measurement Report
UE
UTRAN
MEASUREMENT REPORT
Measurement Control, normal case
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Page17
Contents2. Measurement of Handover2.1 Measurement Control and Measurement Report 2.2 Measurement Phase
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Page18
Measurement Modelparameters parameters
A
Layer 1 filtering
B
Layer 3 filtering
C C'
Evaluation of reporting criteria
D
A is measurement value at the physical layer B is the measurement value after layer 1 filtering at physical layer. The value goes from the physical layer to high layer C is measurement after processing in the layer3 filter C is another measurement value D is measurement report information sent on the radio interface or Iub interface
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Page19
Measurement Quantity
Ec/No
CPICH signal quality
RSCP
CPICH signal level
RSSI
GSM cell signal level
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Page20
Measurement Quantity Configuration
IntraFreqMeasQuantityParameter name: Intra-frequency measure quantity The default value of this parameter is Ec/No
InterFreqMeasQuantityParameter name: Inter-frequency measure quantity The default value of this parameter is Both
MeasQuantityOf3AParameter name: 3A Measure Quantity The default value of this parameter is RSCP
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Page21
Layer 3 filteringFn ! (1 a) Fn 1 a M nWhere:
Fn is the new measurement value after filtering. Fn-1 is the last measurement value after filtering. Mn is the latest measurement value from the physical layer. a = 1/2(k/2) (k is set to Intra-freq meas L3 filter coeff)
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Page22
Layer 3 filtering coefficient
FilterCoefParameter name: Intra-frequency measurement filter coefficient The default value of this parameter is D3
InterFreqFilterCoefParameter name: Inter-frequency measure filter coefficient The default value of this parameter is D3
InterRATFilterCoefParameter name: Inter-RAT filter coefficient The default value of this parameter is D3
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Page23
Measurement Report Mode
Periodic Report Event Trigger Report Event to Periodic Report
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Page24
Contents1. Introduction of Handover 2. Measurement of Handover 3. The Basic Handovers
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Page25
Contents3. The Basic Handovers3.1 Soft Handover 3.2 Intra-frequency Hard Handover 3.3 Inter-frequency Hard Handover 3.4 Inter-RAT Hard Handover 3.5 Blind Handover
Copyright 2006 Huawei Technologies Co., Ltd. All rights reserved.
Page26
Contents3. The Basic Handovers3.1 Soft Handover 3.2 Intra-frequency Hard Handover 3.3 Inter-frequency Hard Handover 3.4 Inter-RAT Hard Handover 3.5 Blind Handover
Copyright 2006 Huawei Technologies Co., Ltd. All rights reserved.
Page27
Brief Introduction of Soft Handover
Characters of Soft Handover
During handover, UE has several RLs with different cells The handover among different cells which are in same RLS can be softer handover
Signals from each RL will be combined in UL and DL.
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Page28
Brief Introduction of Soft Handover
Advantages
Soft handover gain Decrease the possibility of call drop
Disadvantages
More resource needed in downlink it may cause side-effect
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Page29
Measurement of Soft Handover
Measurement quantity
CPICH RSCP CPICH Ec/No
Reporting mode
Periodic reporting Event trigger reporting Event trigger reporting to Periodic reporting
Event type
1A,1B,1C,1D
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Page30
Soft Handover Measurement EventsEvent 1A Description The PCPICH quality of the cells in the monitored set enters the reporting range . This indicates that the quality of a cell is close to the quality of the best cell . A relative high combined gain can be achieved when the cell is added to the active set 1B The PCPICH quality of the cells in the active set leaves the reporting range. This indicates that quality of a cell is much worse than the quality of the best cell. The cell should not stay in the active set 1C A non-active PCPICH becomes better than an active PCPICH. This indicates that the quality of a cell is close to the quality of the best cell. In addition ,the number of cells in the active set has reached the maximum value. The cell replaces the worst cell in the active set ; thus achieving a higher combined gain 1D Event of the change of the best cell
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Page31
The Trigger Algorithm of 1A Event
Event 1A is triggered on the basis of the following formula
10 LogM New CIONew
NA u W 10 Log M i (1 W ) 10 LogM Best ( R1a H 1a / 2), i !1
10 LogM New CIONew
NA W 10 Log M i (1 W ) 10 LogM Best ( R1a H1a / 2), i !1
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Page32
Example of 1A Event
A: signal curve of the best cell in the active set B: signal curve of a cell in the monitoring set C: The 1A curve
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Page33
Key parameters of 1A Event
INTRARELTHDFOR1ACSParameter name: CS service 1A event relative threshold The default value of this parameter is 6 ( 3dB )
INTRARELTHDFOR1APSParameter name: PS service 1A event relative threshold The default value of this parameter is 6 ( 3dB )
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Page34
Key parameters of 1A Event
HYSTFOR1AParameter name: 1A event hysteresis The default value of this parameter is 0( 0dB )
TRIGTIME1AParameter name: 1A event trigger delay time The default value of this parameter is D320 ( 320ms )
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Page35
The Trigger Algorithm of 1B Event
Event 1B is triggered on the basis of the following formula
10 LogM Old CIOOld
NA e W 10 Log M i (1 W ) 10 LogM Best ( R1b H 1b / 2), i !1
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Page36
Example of 1B Event
A: signal curve of the best cell in the active set B: signal curve of a cell in the monitoring set C: The 1B curve
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Page37
Key parameters of 1B Event
INTRARELTHDFOR1BCSParameter name: CS service 1B event relative threshold The default value of this parameter is 12 ( 6dB )
INTRARELTHDFOR1BPSParameter name: PS service 1B event relative threshold The default value of this parameter is 12 ( 6dB )
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Page38
Key parameters of 1B Event
HYSTFOR1BParameter name: 1B event hysteresis The default value of this parameter is 0( 0dB )
TRIGTIME1BParameter name: 1B event trigger delay time The default value of this parameter is D640 ( 640ms )
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Page39
The Trigger Algorithm of 1C Event
Event 1C is triggered on the basis of the following formula
10 LogM New CIONew u 10 LogM InAS CIOInAS H1c / 2,
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Page40
Example of 1C Event
A: signal curve of the best cell in the active set B: signal curve of a cell in the active set C: signal curve of the worst cell in the active set D: signal curve of a cell in the monitoring set E: The 1C curve Copyright 2006 Huawei Technologies Co., Ltd. All rights reserved. Page41
Key parameters of 1C Event
HYSTFOR1CParameter name: 1C event hysteresis The default value of this parameter is 8( 4dB )
TRIGTIME1CParameter name: 1C event trigger delay time The default value of this parameter is D640 ( 640ms )
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Page42
The Trigger Algorithm of 1D Event
Event 1D is triggered on the basis of the following formula
10 LogM Notbest u 10 LogM Best H1d / 2,
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Page43
Example of 1D Event
A: signal curve of the best cell in the active set B: signal curve of a cell in the active set or monitoring set C: Th1D curve
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Key parameters of 1D Event
HYSTFOR1DParameter name: 1D event hysteresis The default value of this parameter is 8( 4dB )
TRIGTIME1DParameter name: 1D event trigger delay time The default value of this parameter is D640 ( 640ms )
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Page45
Other key parameters for SHO
WeightParameter name: Weighted factor The default value of this parameter is 0
SHOQualminParameter name: Min quality THD for SHO The default value of this parameter is -24(-24 dB)
CELLINDIVIDALOFFSETParameter name: Cell offset The default value of this parameter is 0 ( 0dB )
Copyright 2006 Huawei Technologies Co., Ltd. All rights reserved.
Page46
Contents3. The Basic Handovers3.1 Soft Handover 3.2 Intra-frequency Hard Handover 3.3 Inter-frequency Hard Handover 3.4 Inter-RAT Hard Handover 3.5 Blind Handover
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Page47
Brief Introduction of Intra-Frequency Hard Handover
Characters of Intra-Frequency Hard Handover
During handover, UE has only one RL with one cell Switch off the RL with the original cell, then setup the RL with target cell
The frequency of source cell and target cell are same
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Page48
Brief Introduction of Intra-Frequency Handover
Advantages
Enhance the usage efficiency of the OVSF code and hardware
Disadvantages
High call drop possibility because of the intra-frequency interference
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Page49
Key parameters of Intra-frequency Hard handover
BEBITRATETHDParameter name: BE service handover rate threshold The default value of this parameter is 384k
The Parameters about 1D EventTime to trigger Hysteresis
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Page50
Contents3. The Basic Handovers3.1 Soft Handover 3.2 Intra-frequency Hard Handover 3.3 Inter-frequency Hard Handover 3.4 Inter-RAT Hard Handover 3.5 Blind Handover
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Page51
Brief Introduction of Inter-Frequency Handover
Characters of Inter-frequency Hard Handover
The frequency of original cell and source cell are different There is only one RL for the UE The compressed mode is needed
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Page52
Compressed Mode
Purpose
Measure the inter-frequency cell or Inter-RAT cell under FDD mode
Categories
Downlink compressed mode Uplink compressed mode
Realization Methods
SF/2 Higher layer scheduling
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Page53
Measurement of Inter-frequency Handover
Measurement quantity
CPICH RSCP CPICH Ec/No
Reporting mode
Periodic reporting Event trigger reporting Event trigger reporting to Periodic reporting
Event type
2B,2C,2D,2F
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Page54
Inter-frequency Handover Measurement EventsEvent 2D Description When the current signal quality is lower than the preset threshold , the UTRAN enables the compressed mode and starts inter-frequency measurement 2F When the current signal quality is higher than the preset threshold, the UTRAN disables the compressed mode and stops inter-frequency measurement 2B When the current signal is lower than the preset threshold and the signal quality of an inter-frequency neighbouring cell is higher than the preset threshold , the UTRAN trigger an inter-frequency handover based on coverage 2C The estimated quality of a inter-frequency neighbor cell is higher than the preset thresholdCopyright 2006 Huawei Technologies Co., Ltd. All rights reserved. Page55
The Trigger Algorithm of 2D EventEvent 2D is triggered on the basis of the following formula
QUsed e TUsed 2 d H 2 d / 2
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Page56
Key parameters of of 2D Event
InterFreqCSThd2DEcN0Parameter name: Inter-freq CS measure start Ec/No THD The default value of this parameter is -14 dB
InterFreqPSThd2DEcN0Parameter name: Inter-freq PS measure start Ec/No THD The default value of this parameter is -14 dB
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Page57
Key parameters of of 2D Event
InterFreqCSThd2DRSCPParameter name: Inter-freq CS measure start RSCP THD The default value of this parameter is -95 dBm
InterFreqPSThd2DRSCPParameter name: Inter-freq PS measure start RSCP THD The default value of this parameter is -95 dBm
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Page58
Key parameters of 2D Event
HYSTFOR2DParameter name: 2D event hysteresis The default value of this parameter is 4( 2dB )
TRIGTIME2DParameter name: 2D event trigger delay time The default value of this parameter is D320 ( 320ms )
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Page59
The Trigger Algorithm of 2F Event
Event 2F is triggered on the basis of the following formula
QUsed u TUsed 2 f H 2 f / 2
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Key parameters of 2F Event
InterFreqCSThd2FEcN0Parameter name: Inter-freq CS measure stop Ec/No THD The default value of this parameter is -12 dB
InterFreqPSThd2FEcN0Parameter name: Inter-freq PS measure stop Ec/No THD The default value of this parameter is -12 dB
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Page61
Key parameters of 2F Event
InterFreqCSThd2FRSCPParameter name: Inter-freq CS measure stop RSCP THD The default value of this parameter is -92 dBm
InterFreqPSThd2FRSCPParameter name: Inter-freq PS measure stop RSCP THD The default value of this parameter is -92 dBm
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Page62
Key parameters of 2F Event
HYSTFOR2FParameter name: 2F event hysteresis The default value of this parameter is 4( 2dB )
TRIGTIME2FParameter name: 2F event trigger delay time The default value of this parameter is D1280 ( 1280ms )
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Page63
The Trigger Algorithm of 2B EventEvent 2B is triggered on the basis of the following formula
QNon used u TNon used 2b H 2b / 2
, and
QUsed e TUsed 2b H 2b / 2
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Page64
Key parameters of 2B Event
InterFreqCovHOCSThdEcN0Parameter name: Inter-freq CS target frequency trigger Ec/No THD The default value of this parameter is -12 dB
InterFreqCovHOPSThdEcN0Parameter name: Inter-freq PS target frequency trigger Ec/No THD The default value of this parameter is -12 dB
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Page65
Key parameters of 2B Event
InterFreqCovHOCSThdRSCPParameter name: Inter-freq CS target frequency trigger RSCP THD The default value of this parameter is -92 dBm
InterFreqCovHOPSThdRSCPParameter name: Inter-freq PS target frequency trigger RSCP THD The default value of this parameter is -92 dBm
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Page66
Key parameters of 2B Event
IFHOUsedFreqCSThdEcN0Parameter name: Inter-freq CS Used frequency trigger Ec/No THD The default value of this parameter is -12dB
IFHOUsedFreqPSThdEcN0Parameter name: Inter-freq PS Used frequency trigger Ec/No THD The default value of this parameter is -12 dB
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Page67
Key parameters of 2B Event
IFHOUsedFreqCSThdRSCPParameter name: Inter-freq CS Used frequency trigger RSCP THD The default value of this parameter is -92dBm
IFHOUsedFreqPSThdRSCPParameter name: Inter-freq PS Used frequency trigger RSCP THD The default value of this parameter is -92 dBm
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Page68
Key parameters of 2B Event
HYSTFOR2BParameter name: 2B event hysteresis The default value of this parameter is 4( 2dB )
TRIGTIME2BParameter name: 2B event trigger delay time The default value of this parameter is D0 ( 0ms )
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Page69
The Trigger Algorithm of 2C EventEvent 2C is triggered on the basis of the following formula
QNon used u TNon used 2c H 2c / 2
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Page70
Key parameters of 2C Event
InterFreqNCovHOThdEcN0Parameter name: Inter-freq CS target frequency trigger Ec/No THD The default value of this parameter is -16 dB
Hystfor2CParameter name: 2C hysteresis The default value of this parameter is 6 (3dB)
TrigTime2CParameter name: 2C event trigger delay time The default value of this parameter is D640 (640ms)
Copyright 2006 Huawei Technologies Co., Ltd. All rights reserved.
Page71
Contents3. The Basic Handovers3.1 Soft Handover 3.2 Intra-frequency Hard Handover 3.3 Inter-frequency Hard Handover 3.4 Inter-RAT Hard Handover 3.5 Blind Handover
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Page72
Brief Introduction of Inter-RAT Handover
Characters of Inter-RAT HandoverBased on handover directions, inter-RAT handover is of two types:
UMTS->GSM handover UMTS->GSM coverage-based handover UMTS->GSM load-based handover UMTS->GSM service-based handover
GSM->UMTS handover
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Page73
Brief Introduction of Inter-RAT Handover
AdvantagesFor coverage, it can solve the problems from one system to another system For capacity, it can enhance the utilizing efficiency of old equipments(2G->3G)
DisadvantagesThe flow is complicated, and it demands higher compatibility for equipments Demands more complicated UE
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Page74
Measurement of Inter-RAT Handover
Measurement quantityCPICH_Ec/N0 CPICH_RSCP BOTH
Reporting modePERIODICAL_REPORTING EVENT_TRIGGER
Event type2D, 2F 3A, 3C
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Page75
Inter-RAT Handover Measurement EventsEvent 2D Description When the signal quality of the currently used frequency is lower than the preset threshold, the RNC enables the compressed mode and starts inter-RAT measurement. 2F When the signal quality of the currently used frequency is higher than the preset threshold, the RNC disables the compressed mode and stops inter-RAT measurement. 3A When the signal quality of the currently used UMTS frequency is lower than the preset threshold while the signal quality of any other system is higher than the preset threshold, the RNC triggers UMTS->GSM handover based on coverage. 3C When the signal quality of any other system is higher than the preset threshold, the RNC triggers UMTS->GSM handover based on load or service.
Copyright 2006 Huawei Technologies Co., Ltd. All rights reserved.
Page76
The Trigger Algorithm of 2D Event
Event 2D is triggered on the basis of the following formula:
Q Used e TUsed2d - H 2d / 2
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Page77
Key Parameters of 2D Event
INTERRATCSTHD2DECNOParameter name: Inter-RAT CS measure start Ec/No THD The default value of this parameter is -14 ( -14 dB )
INTERRATPSTHD2DECNOParameter name: Inter-RAT PS measure start Ec/No THD The default value of this parameter is -15 ( -15 dB )
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Page78
Key Parameters of 2D Event
INTERRATCSTHD2DRSCPParameter name: Inter-RAT CS measure start RSCP THD The default value of this parameter is -100 ( -100 dBm )
INTERRATPSTHD2DRSCPParameter name: Inter-RAT PS measure start RSCP THD The default value of this parameter is -110 (-110 dBm )
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Page79
Key Parameters of 2D Event
HYSTFOR2DParameter name: 2D hysteresis The default value of this parameter is 4 ( 2 dB )
TRIGTIME2DParameter name: 2D event trigger delay time The default value of this parameter is D320 (320 ms )
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Page80
The Trigger Algorithm of 2F Event
Event 2F is triggered on the basis of the following formula:
Q Used u TUsed2f H 2f / 2
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Page81
Key Parameters of 2F Event
INTERRATCSTHD2FECNOParameter name: Inter-RAT CS measure stop Ec/No THD The default value of this parameter is -12 ( -12 dB )
INTERRATPSTHD2FECNOParameter name: Inter-RAT PS measure stop Ec/No THD The default value of this parameter is -13 ( -13 dB )
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Page82
Key Parameters of 2F Event
INTERRATCSTHD2FRSCPParameter name: Inter-RAT CS measure stop RSCP THD The default value of this parameter is -97 ( -97 dBm )
INTERRATPSTHD2FRSCPParameter name: Inter-RAT PS measure stop RSCP THD The default value of this parameter is -107 (-107 dBm )
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Page83
Key Parameters of 2F Event
HYSTFOR2FParameter name: 2F hysteresis The default value of this parameter is 4 ( 2 dB )
TRIGTIME2FParameter name: 2F event trigger delay time The default value of this parameter is D1280 (1280 ms )
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Page84
The Trigger Algorithm of 3A Event
Event 3A is triggered on the basis of the following formula:
Q Used e TUsed3a H 3a / 2M OtherRat CIOOtherRat u TOtherRat H 3a / 2
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Page85
Key Parameters of 3A Event
IRHOUSEDFREQCSTHDECNOParameter name: Inter-RAT CS Used frequency trigger Ec/No THD The default value of this parameter is -12 ( -12 dB )
IRHOUSEDFREQPSTHDECNOParameter name: Inter-RAT PS Used frequency trigger Ec/No THD The default value of this parameter is -13 ( -13 dB )
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Page86
Key Parameters of 3A Event
IRHOUSEDFREQCSTHDRSCPParameter name: Inter-RAT CS Used frequency trigger RSCP THD The default value of this parameter is -97 ( -97 dBm )
IRHOUSEDFREQPSTHDRSCPParameter name: Inter-RAT PS Used frequency trigger RSCP THD The default value of this parameter is -107 (-107 dBm )
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Page87
Key Parameters of 3A Event
INTERRATCOVHOCSTHDParameter name: Inter-RAT CS handover decision THD The default value of this parameter is 16 ( -95 dBm )
INTERRATCOVHOPSTHDParameter name: Inter-RAT PS handover decision THD The default value of this parameter is 16 ( -95 dBm )
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Page88
Key Parameters of 3A Event
HYSTFOR3AParameter name: 3A hysteresis The default value of this parameter is 4 ( 2 dB )
TRIGTIME3AParameter name: 3A event trigger delay time The default value of this parameter is D0 ( 0 ms )
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Page89
Key Parameters of 3A Event
CELLINDIVIDALOFFSETParameter name: Cell individual offset The default value of this parameter is 0 ( 0 dB )
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Page90
The Trigger Algorithm of 3C Event
Event 3C is triggered on the basis of the following formula:
M OtherRat CIOOtherRat u TOtherRat H 3c / 2
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Page91
Key Parameters of 3C Event
INTERRATNCOVHOCSTHDParameter name: Inter-RAT CS handover decision THD The default value of this parameter is 21 ( -90 dBm )
INTERRATNCOVHOPSTHDParameter name: Inter-RAT PS handover decision THD The default value of this parameter is 21 (-90 dBm )
Copyright 2006 Huawei Technologies Co., Ltd. All rights reserved.
Page92
Key Parameters of 3C Event
HYSTFOR3CParameter name: 3C hysteresis The default value of this parameter is 0 ( 0 dB )
TRIGTIME3CParameter name: 3C event trigger delay time The default value of this parameter is D640 ( 650 ms )
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Page93
Key Parameters of 3C Event
PENALTYTIMEFORINTERRATHOParameter name: Inter-RAT handover failure penalty timer length The default value of this parameter is 30 ( 30 s )
INTERRATHOATTEMPTSParameter name: Inter-RAT handover max attempt times The default value of this parameter is 16
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Page94
Key Parameters of 3C Event
INTERRATMEASTIMEParameter name: Inter-RAT measure timer length [s] The default value of this parameter is 60 ( 60 s )
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Page95
Contents3. The Basic Handovers3.1 Soft Handover 3.2 Intra-frequency Hard Handover 3.3 Inter-frequency Hard Handover 3.4 Inter-RAT Hard Handover 3.5 Blind Handover
Copyright 2006 Huawei Technologies Co., Ltd. All rights reserved.
Page96
Blind Handover Measurement
Blind handover means UE can directly handover to the neighboring cell without measuring it.
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Page97
The Trigger Algorithm of 1F Event
10 LogM Old e T1 f H 1 f / 2
Where:MOld is the measurement value of the cell signal that becomes worse T1f is the absolute threshold of event 1F. H1f is the hysteresis value of event 1F.
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Page98
The Trigger Algorithm of 1F EventMeasurement Quantity
Cell 11F Trigger Delay Time Absolute Threshold T1f Hysteresis H1f /2
TimeReporting event 1F
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Page99
Key Parameters of Event 1F
INTRAABLTHDFOR1FECNOParameter name: 1F event absolute EcNo threshold The recommended value is -24 dB
INTRAABLTHDFOR1FRSCPParameter name: 1F event absolute RSCP threshold The recommended value is -115 dBm
Copyright 2006 Huawei Technologies Co., Ltd. All rights reserved.
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Key Parameters of Event 1F
HYSTFOR1FParameter name: 1F hysteresis The recommended value is 8, namely 4 dB
TRIGTIME1FParameter name: 1F event trigger delay time The recommended value is D640, namely 640 ms
Copyright 2006 Huawei Technologies Co., Ltd. All rights reserved.
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Blind Handover Decision
After receiving event 1F of best cell from UE, the RNC would check if blind handover neighbor is configured for the cell.
If multiple blind handover neighbors are configured, the RNC would perform blind handover to the target cell with the highest priority
Copyright 2006 Huawei Technologies Co., Ltd. All rights reserved.
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Key Parameters of Blind Handover
BLINDHOFLAGParameter name: Blind handover flag The default value is FALSE
BLINDHOPRIOParameter name: Blind handover Priority The value is set according to actual situation.
Copyright 2006 Huawei Technologies Co., Ltd. All rights reserved.
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