load balance feature guide r12
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Load Balance Feature Guide R12TRANSCRIPT
Load Balance Feature Guide
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Load Balance Feature Guide
ZTE Confidential Proprietary 1
Load Balance Feature Guide
Version Date Author Reviewer Revision History
V7.0 2012-3-13 Liu Fulei Wu Xiuling
1) Added “the function that when RRC signaling
setup on DCH, HSDPA load balance strategy
can be used” in Section 3.6.
2) Added the parameter that controls the factors
used in HSDPA throughput in Section 3.1.2.
3) Added Chapter 8 “strategy of Balance
Failure”.
4) Added “Directed retry from 3G to 2G is based
on 3G cell signal quality” in Section 3.2.
5) Modified the parameter that controls the
factors used in HSDPA throughput in Section
3.1.2.1.
6) Added 3.1.2.2 “Balance Based on HSPA User
Number”.
7) Added Chapter 9, “UTRAN -> EUTRAN
service balance”.
V8.0 2012-11-27 Liu Fulei Zheng Dan
1) Modified coupling with handover in Section 7.
2) Modified service category in Section 4.1.
3) Added 3.9 “Load-based Multi-carrier
Interoperation in Handover/Call
re-establishment procedure”; 4.4
“Service-based Multi-carrier Interoperation in
Handover/Call re-establishment procedure”;
5.2.4 “HSPA+ capability-based Multi-carrier
Interoperation in Handover/Call
re-establishment procedure”
V8.5 2013-11-22 Liu Fulei Zheng Dan
1. Added PS+CS service balance strategy in
Section 4.2.
2. Balance based on HSPA user number is
improved. Modified Section 3.1.2.2 and
3.1.2.1.
3. Added Feature ID
Load Balance Feature Guide
ZTE Confidential Proprietary 2
© 2014 ZTE Corporation. All rights reserved.
ZTE CONFIDENTIAL: This document contains proprietary information of ZTE and is not to be disclosed or used
without the prior written permission of ZTE.
Due to update and improvement of ZTE products and technologies, information in this document is subjected to
change without notice.
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ZTE Confidential Proprietary 3
TABLE OF CONTENTS
1 Function Attribute ............................................................................................. 9
2 Overview ............................................................................................................ 9
2.1 ZWF21-04-011 Load Balancing ........................................................................... 9
2.2 ZWF21-04-022 Frequency Priority ....................................................................... 9
2.3 ZWF23-04-003 Load Balance for HSDPA Service ............................................. 10
2.4 ZWF23-05-020 Directed Retry Between HS-DSCH and DCH ............................ 10
2.5 ZWF25-04-003 Load Balance for HSUPA Service ............................................. 10
2.6 ZWF25-05-003 Directed Retry Between E-DCH and DCH ................................. 11
3 Load-based Multi-carrier Interoperation ........................................................ 11
3.1 Single/Multi-mode System, Load Balance Strategy Intra-RNC ........................... 13
3.1.1 Strategy for R99 ................................................................................................. 13
3.1.2 Strategy for HSPA.............................................................................................. 17
3.2 Multi-mode System, Load Balance Strategy Among Inter-system ...................... 28
3.3 Single/Multi-mode System, Load Balance Strategy Inter-RNC ........................... 31
3.4 Single/Multi-mode System, Load Balance Strategy Among Inter-system ........... 31
3.5 Load Balance Strategy When Multi System Exist ............................................... 32
3.6 Load-based Multi-carrier Interoperation in Initial RRC procedure ....................... 33
3.7 Load-based Multi-carrier Interoperation in RAB assignment .............................. 34
3.8 Load-Based Multi-carrier Interoperation in Call holding procedure ..................... 35
3.9 Load-Based Multi-carrier Interoperation in Handover/Call re-establishment
procedure .......................................................................................................... 36
4 Service-based Multi-carrier Interoperation .................................................... 36
4.1 Service-based Multi-carrier Interoperation in Initial RRC procedure ................... 37
4.2 Service-based Multi-carrier Interoperation in RAB Assignment .......................... 41
4.3 Service-based Multi-carrier Interoperation in Call holding procedure ................. 43
4.4 Service-based Multi-carrier Interoperation in Handover/Call re-establishment
procedure .......................................................................................................... 44
5 HSPA+ Feature Related Balance .................................................................... 44
5.1 DC Traffic Redirection ........................................................................................ 44
5.2 HSPA+ capability-based Multi-carrier Interoperation .......................................... 45
5.2.1 HSPA+ capability-based Multi-carrier Interoperation in Initial RRC procedure ... 45
5.2.2 HSPA+ capability-based Multi-carrier Interoperation in RAB Assignment........... 45
5.2.3 HSPA+ capability-based Multi-carrier Interoperation in Call holding procedure .. 46
5.2.4 HSPA+ capability-based Multi-carrier Interoperation in Handover/Call
re-establishment procedure ............................................................................... 46
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6 Coupling of Load-based, HSPA+ capability-based and Service-based
Multi-carrier Interoperations ............................................................................................. 46
7 Measurement -based Multi-carrier Interoperation ......................................... 47
8 Strategy of Balance Failure ............................................................................ 48
9 UTRAN -> EUTRAN Service Balance.............................................................. 48
10 Configuration and Parameters ....................................................................... 49
10.1 Parameter List ................................................................................................... 49
10.2 Parameter Configuration .................................................................................... 53
10.2.1 Load Balance Switch of Initial RRC Procedure .................................................. 53
10.2.2 Load Balance Switch of RAB Assignment Procedure ......................................... 53
10.2.3 Load Balance Switch of Call holding Procedure ................................................. 53
10.2.4 Load balance switch for downlink power ............................................................ 54
10.2.5 Load Balance Switch for Uplink Interference ...................................................... 54
10.2.6 Load Balance Switch for Code ........................................................................... 54
10.2.7 Load Balance Switch for HSDPA Throughput .................................................... 55
10.2.8 Downlink Power Weight for Load Balance ......................................................... 55
10.2.9 Uplink Interference Weight for Load Balance ..................................................... 55
10.2.10 Code Weight for Load Balance .......................................................................... 56
10.2.11 HSDPA Throughput Weight for Load Balance .................................................... 56
10.2.12 UTRAN Downlink Available Load Balance Threshold (Power) for CS ................ 56
10.2.13 Inter-RAT Downlink Available Load Balance Threshold (Power) for CS ............. 57
10.2.14 UTRAN Downlink Available Load Balance Threshold (Power) for R99 PS ......... 57
10.2.15 Permitted Payload Difference Downlink Available Load Threshold in
Inter-frequency Cells (Power) ............................................................................ 57
10.2.16 UTRAN Uplink Available Load Balance Threshold (Interference ) for CS ........... 58
10.2.17 Inter-system Uplink Available Load Balance Threshold (Interference) for CS ..... 58
10.2.18 UTRAN Uplink Available Load Balance Threshold (Interference) for R99 PS ..... 59
10.2.19 Permitted Payload Difference Uplink Available Load Threshold in
Inter-frequency Cells (Interference) .................................................................... 59
10.2.20 UTRAN Downlink Available Load Balance Threshold (Code) for CS .................. 59
10.2.21 UTRAN Downlink Available Load Balance Threshold (Code) for R99 PS .......... 60
10.2.22 Permitted Payload Difference Downlink Available Load Threshold in
Inter-frequency Cells (Code) .............................................................................. 60
10.2.23 UTRAN Downlink Available Load Balance Threshold (HSDPA Throughput) for
HSDPA .............................................................................................................. 61
10.2.24 Permitted Payload Difference Downlink Available Load Threshold in
Inter-frequency Cells (HSDPA Throughout) ....................................................... 61
10.2.25 Service Balance Switch of Initial RRC Procedure............................................... 61
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10.2.26 Service Balance Switch of RAB Assignment Procedure ..................................... 62
10.2.27 Service Balance Switch of Call holding Procedure ............................................. 62
10.2.28 CS Traffic Preferred Indicator ............................................................................ 62
10.2.29 R99 PS Traffic Preferred Indicator ..................................................................... 63
10.2.30 HS PS Traffic Preferred Indicator ....................................................................... 63
10.2.31 Share Cover Indication (utranRelation) .............................................................. 63
10.2.32 Share Cover Indication (gsmRelation)................................................................ 64
10.2.33 HSPA Support Method(utranCell) ...................................................................... 64
10.2.34 HSPA Support Method(externalUtranCell) ......................................................... 64
10.2.35 CS Balance Switch of RAB Assignment Procedure............................................ 64
10.2.36 Switch of CS Handover for CS+PS in Multi-Carrier Scenario ............................. 65
10.2.37 Dual Carrier Redirection Strategy Switch ........................................................... 65
10.2.38 Cpich RSCP Threshold for Dual Carrier HSDPA Balance .................................. 65
10.2.39 Cpich EcNo Threshold for Dual Carrier HSDPA Balance ................................... 66
10.2.40 Dual Carrier Balance Switch of Initial RRC Procedure ....................................... 66
10.2.41 HSPA+ Balance Switch of Call Holding Procedure ............................................ 66
10.2.42 HSPA+ Balance Switch of RAB Assignment Procedure ..................................... 66
10.2.43 HSPA+ Capability Indicator ................................................................................ 67
10.2.44 HSPA+ Balance Priority ..................................................................................... 67
10.2.45 Inter-Frequency Balance Switch Based on Measurement .................................. 67
10.2.46 Inter-Frequency Balance Switch Based on Measurement with Overlapping or
Covering Relation .............................................................................................. 68
10.2.47 User Number with Compressed Mode Activation for Balance Strategy Based On
Measurement ..................................................................................................... 68
10.2.48 Timer of Deactivate Compressed Mode for Balance Strategy Based On
Measurement ..................................................................................................... 69
10.2.49 Cpich Ec/N0 Threshold for Blind Handover ........................................................ 69
10.2.50 Cpich RSCP Threshold for Blind Handover ........................................................ 69
10.2.51 Load Balance Switch for Bandwidth ................................................................... 70
10.2.52 HSUPA Throughput Weight for Load Balance .................................................... 70
10.2.53 UTRAN Uplink Available Load Balance Threshold (HSUPA Throughput) for
HSUPA .............................................................................................................. 70
10.2.54 Permitted Payload Difference Available Load Threshold in Inter-frequency Cells
(HSUPA Throughput) ......................................................................................... 71
10.2.55 Equivalent HSPA Users ..................................................................................... 71
10.2.56 GSM Cell‟s Carrier Number ............................................................................... 71
10.2.57 User Number Offset of UTRAN for Balance ....................................................... 72
10.2.58 User Number Offset of GSM in Multi-Mode System for Balance ........................ 72
10.2.59 User Number Offset of GSM for Balance ........................................................... 72
10.2.60 TCP Load Low Threshold .................................................................................. 73
10.2.61 TCP Load Middle Threshold .............................................................................. 73
10.2.62 TCP Load High Threshold .................................................................................. 73
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10.2.63 RTWP Load Low Threshold ............................................................................... 74
10.2.64 RTWP Load Middle Threshold ........................................................................... 74
10.2.65 RTWP Load High Threshold .............................................................................. 74
10.2.66 HSDPA User Number Low Threshold ................................................................ 75
10.2.67 HSDPA User Number Middle Threshold ............................................................ 75
10.2.68 HSUPA User Number Low Threshold ................................................................ 75
10.2.69 HSUPA User Number Middle Threshold ............................................................ 76
10.2.70 MBMS User Number Low Threshold .................................................................. 76
10.2.71 MBMS User Number Middle Threshold .............................................................. 76
10.2.72 Signal User Number Low Threshold .................................................................. 77
10.2.73 Signal User Number Middle Threshold ............................................................... 77
10.2.74 Code Load Low Threshold ................................................................................. 77
10.2.75 Code Load Middle Threshold ............................................................................. 78
10.2.76 CE Load Low Threshold .................................................................................... 78
10.2.77 CE Load Middle Threshold ................................................................................. 78
10.2.78 Load Balance Scene .......................................................................................... 79
10.2.79 Switch of HSDPA Load Balance for Signaling on DCH in RRC Connection
Procedure .......................................................................................................... 79
10.2.80 Code Factor in HSDPA Throughput Load Balance............................................. 79
10.2.81 Power Factor in HSDPA Throughput Load Balance ........................................... 80
10.2.82 Bandwidth Factor in HSDPA Throughput Load Balance .................................... 80
10.2.83 Switch of Optimization When Load Balance Fail ................................................ 80
10.2.84 Cpich Ec/NO Threshold for Directed Retry Triggered by Inter-RAT Balancing ... 81
10.2.85 Cpich RSCP Threshold for Directed Retry Triggered by Inter-RAT Balancing .... 81
10.2.86 Load Balance Strategy for HSPA Service .......................................................... 82
10.2.87 Load Balance Switch for HSUPA Throughput .................................................... 82
10.2.88 Load Balance Switch for HSDPA User Number ................................................. 82
10.2.89 UTRAN Downlink Available Load Balance Threshold (HSDPA User Number) for
HSPA ................................................................................................................. 82
10.2.90 Permitted Payload Difference Downlink Available Load Threshold in
Inter-frequency Cells .......................................................................................... 83
10.2.91 UTRAN to EUTRAN balance switch ................................................................... 83
10.2.92 Cell Reserved Parameter 1 ................................................................................ 83
10.2.93 Load Balance Switch of Handover and Call Reestablishment Procedure ........... 84
10.2.94 Service Balance Switch of Handover and Call Reestablishment Procedure ....... 84
10.2.95 HSPA+ Balance Switch of Handover and Call Reestablishment Procedure ....... 84
10.2.96 PS+CS balance switch ....................................................................................... 85
11 Counter And Alarm .......................................................................................... 85
11.1 Counter List ....................................................................................................... 85
11.2 Alarm List ........................................................................................................... 87
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12 Glossary ........................................................................................................... 87
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TABLES
Table 3-1 Services and target cell types which can carry the services ...............................35
Table 4-1 Candidate cell list selection for CS service .........................................................38
Table 4-2 Candidate cell list selection for PS service .........................................................39
Table 4-3 Table of Cell Types Supported by Current Services of UE .................................41
Table 4-4 Table of Sequence of Cells of Services ..............................................................42
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1 Feature Attributes
System version: [RNCV3.12.10/RNCV4.12.10, Node B V4.12.10]
Attribute: [Optional]
Involved NEs:
UE Node B RNC MSCS MGW SGSN GGSN HLR
√ √ √ - - - - -
Note:
*-: Not involved.
*√: Involved.
Dependency: [None]
Mutual exclusion: [None]
Note: [None]
2 Overview
2.1 ZWF21-04-011 Load Balancing
Load balancing indicates load-based multi-carrier interoperation. Its main purpose is to
deploy the inter-cell traffic based on the load of cell and the neighboring cell configuration
(ShareCover, GsmShareCover) reasonably, and use the system resources effectively to
enhance the system capacity and QoS.
2.2 ZWF21-04-022 Frequency Priority
The feature provides the function that allows each cell to support HSDPA or HSUPA or
not (HspaSptMeth), and each cell can be set to be preferred to voice service preferred,
data service preferred or not preferred (CsTrafPrefInd/r99PsTrafPrefInd/hsTrafPrefInd).
During RRC connection setup, RAB assignment, handover, cell reselection and channel
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migration procedures, the RNC will choose an appropriate cell as target cell according to
service type and UE capability.
The frequency priority feature considers the current load of each cell in each frequency
layer, avoiding congestion because of heavy traffic in a cell.
2.3 ZWF23-04-003 Load Balance for HSDPA Service
The RNC supports HSDPA load balancing between carriers in a UMTS network or
between UMTS and GSM when the HSDPA function is introduced. Besides downlink
power factor, the HSDPA capability of Node B and UE are also considered for HSDPA
service load balancing.
2.4 ZWF23-05-020 Directed Retry Between HS-DSCH
and DCH
The RNC allows each cell to be configured with different attributes, for example, some
cells support HSDPA service but not R99 service, which means service is provided by
HS-DSCH but not DCH. If the network is deployed with two or more carriers, one of
which is set to be equipped with at least one dedicated HSDPA carrier and one dedicated
R99 carrier, and radio resources should be allocated into different carriers according to
services attributes. If user‟s access frequency is different from the one which a service
needs, the RNC will perform handover between carriers to retry services into frequency
which the service needs.
2.5 ZWF25-04-003 Load Balance for HSUPA Service
The RNC supports HSUPA load balancing between carriers in a UMTS network or
between UMTS and GSM when the HSUPA function is introduced. Besides RTWP factor,
the HSUPA capability of Node B and UE are also considered for HSUPA service load
balancing.
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2.6 ZWF25-05-003 Directed Retry Between E-DCH and
DCH
In the case of network deployed with two or more carriers, if at least one is a dedicated
HSUPA carrier and one is a dedicated R99 carrier, radio resources should be allocated
into different carriers according to service attributes. If user‟s access frequency is
different from the one which a service needs, RNC will perform handover between
carriers to retry services into frequency which the service needs.
3 Load-based Multi-carrier Interoperation
1. Structure of load balance
According to 3GPP, a lot of load information cannot be exchanged between UMTS and
GSM or intra-UMTS. After a multi-mode system is introduced, intra-interface can be
defined in the multi-mode system, cell‟s load can be evaluated more precisely. The
network structure is shown below.
UMTS F1
Single/multi- mode
UMTS F2
GSM
UMTS F3
Single/multi- mode
GSM
12
3
4
1: Single/Multi-mode System, Load Balance Strategy Intra-RNC
2: Multi-mode System, Load Balance Strategy Among Inter-system
3: Single/Multi-mode System, Load Balance Strategy Inter-RNC
4: Single/Multi-mode System, Load Balance Strategy Among Inter-system
The four strategies are described in later chapters.
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2. Service category of load balance
There are four kinds of services, R99 CS, R99 PS, HSDPA and HSUPA. Considering the
ability of exchanging load information and the service which a GSM system can provide,
scenarios are listed below.
1 2 3 4
R99 CS
R99 PS
HSDPA
HSUPA
Notes: considered , not considered
3. Phase of load balance
Load-based multi-carrier interoperation selects a target cell preferably in the Initial RRC
procedure, RAB assignment, and call holding procedure, rather than triggering the
handover actively. Specifically, the RNC puts the source cell to which the UE belongs
and its neighboring cells with “Overlap” or “Covers” (ShareCover) relationship into the
target cell list. The cell with the lowest load in the list is selected as the target cell for
access or handover. The phases are shown as follows.
1 2 3 4
Initial RRC procedure
RAB assignment
Call holding procedure
Initial RRC procedure involves Initial RRC procedure.
RAB assignment involves the first RAB assignment.
Call holding procedure involves handover, relocation from other systems or RNC to
local RNC, call re-establishment triggered by CELL UPDATE, state transition from
non-CELL_DCH to CELL_DCH.
In the three scenarios, related functions are controlled by three switches: InitRrcLBSw,
RabAssLBSw, and CallHoldLBSw.
4. Scenario of load balance
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Different scenarios need to be configured with different parameter values. Load balance
scenario (LoadBalanceScene) is defined to index different templates.
3.1 Single/Multi-mode System, Load Balance Strategy
Intra-RNC
As resource can be completely used by HSPA, the R99 and HSPA use different load
balance strategies. For R99, resources are divided into hard resource and soft resource.
For HSPA, HS throughput is used to evaluate related load factors.
3.1.1 Strategy for R99
For R99, resources are divided into hard resource and soft resource. If hard resource is
limited, a UE cannot access to this cell. While soft resource might be changed according
to other factors, for example, signal. Consequently, hard resource will be evaluated
before soft resource.
1. Hard resource evaluation
Currently, hard resource indicates transmission band, controlled by LdBalBwSwch.
If transmission band is limited and a UE cannot access to this cell, as a result, this cell
will be sorted in to hard-resource-limited list, otherwise, to hard-resource-unlimited list.
The neighboring cells with “Overlap” or “Covers” (ShareCover) relationship are sorted
into hard-resource-limited list and hard-resource-unlimited list separately.
Hard-resource-unlimited list is in front of hard-resource-limited list. Cells in
hard-resource-limited list are ranked in ascending order according to load. Cells in
hard-resource-unlimited list will be further evaluated according to soft resource.
2. Soft resource evaluation
Cells in hard-resource-unlimited list will be further evaluated according to soft resource,
which includes uplink interference (UlLdBalPwrSwch), downlink power
(DlLdBalPwrSwch) and code resource (LdBalCdSwch).
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i. Uplink interference
The uplink interference of a cell uses the RTWP (HSPA cells use uplink payload) as the
load evaluation criterion.
Uplink payload (UlRtwpEffLoad) = UL Base Noise + load from UL DCH + load from non
scheduled E-DCH + load from GBR data rate of scheduled E-DCH.
Refer to <ZTE UMTS Admission Control Feature Guide>.
Uplink available interference is calculated as follows:
Uplink available interference (AvailableLoad1) = 100%-uplink payload (UlRtwpEffLoad)
When the uplink available interference is less than the threshold, CS (UlLdThdCs), R99
PS (UlLdThdR99Ps), the available interference of the cell is little and the current load of
the cell is heavy.
ii. Downlink power
The downlink power of a cell uses the TCP (HSPA cells use downlink payload) as the
load evaluation criterion.
Snum
i
irquiredPoweHSDSCHwerNOHSDSCHPo
0
ReTCP_Load
Where,
NOHSDSCHPower refers to the Transmitted carrier power of all codes not used for
HS-PDSCH or HS-SCCH transmission that is reported by the Node B.
indicates the HS-DSCH Required Power of the scheduling
priority of the current cell.
Downlink available power is calculated as follows:
Downlink available power (AvailableLoad2) =100%- TCP_Load
HSDSCHRequiredPoweri
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When the downlink available power is less than the threshold, CS (DlPwrThdCs), R99
PS (DlPwrThdR99Ps), it means that available the power is small and the current load of
the cell is heavy.
iii. Code resource
Downlink code resource is evaluated by calculating the proportion of used codes to the
total codes. Then, take SF = 128 as the statistic granularity of the code resource.
Because the HSDPA is shared, hence the occupancy of non-HSPDSCHs and minimum
necessary HSPDSCHs is only calculated.
The code load is measured by the channel code usage:
Code Usage = number of Non HS-PDSCH occupied SF128+MinHspdschNum*128/16
Where,
MinHspdschNum = Max (MinHspdschNum in OMCR, MinHspdschNumbyGBR). See
<ZTE UMTS Code Resource Feature Guide V3.0 CHS>.
The load of code resource is, CodeLoadLev = OccuCodeNum/128*100%
Downlink available code resource is calculated as follows,
Downlink available code resource (AvailableLoad3) = 100%- CodeLoadLev
When the amount of downlink available code resources is less than the threshold, CS
(DlCdThdCs), R99 PS (DlCdThdR99Ps), the load of the cell is heavy.
iv. Coupling of factors
When evaluating the load of cell, the load weight, load, and load threshold of the three
factors are taken into account to calculate the cell overall load. See the following
calculation method.
The meanings of the parameters are as follows,
k
i i i
i 1
LoadWeight AvailableLoad AvailableLoadThrd *Weight
( )
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k indicates the number of factors that are considered in load balancing. The current value
is 3, which is uplink interference, downlink power, and code resources.
AvailableLoad is the available load of an evaluated cell. If the evaluated cell is a source
cell, AvailableLoad is equal to the actual available load plus Delta; otherwise it is equal
to the actual available load.
AvailableThrdLoad is the available load balancing threshold configured by OMC. The
threshold is differentiated by service, for CS and R99 PS. (i) For a source cell, the
threshold of the source cell is taken; for a target cell, the threshold of the target cell is
taken. (ii) Each service uses its corresponding threshold. (iii) In the initial RRC procedure,
service is recognized by establishment cause. In RAB assignment, it only indicates the
first RAB; not considering multi-RAB. In call holding procedure, if there is multi-RAB, the
threshold of R99 CS is used prior to R99 PS. (iv) Only threshold is differentiated by
services; while other parameters are not related to services.
Delta indicates the load balancing threshold difference (corresponds to ExtraCDeltaTru,
ExtraCDeltaTrd, ExtraCDeltaCdTrd configured in the source cell) of the source cell
configured by OMC.
Weight indicates the weight (corresponds to UlLdBalPwrWeight, DlLdBalPwrWeight,
LdBalCdWeight configured in the source cell) of each factor. Code resource, downlink
power, and uplink interference are controlled by switches: LdBalCdSwch,
DlLdBalPwrSwch, and UlLdBalPwrSwch. When a factor is switched OFF, it will not be
considered in load balancing and its weight is invalid (0). The sum of each factor‟s
weights (DlLdBalPwrWeight, UlLdBalPwrWeight, and LdBalCdWeight) is 1, which is
ensured by the RNC. If all of the three factors are switched to OFF, load balancing is not
performed.
LoadWeight indicates the evaluation value. A large value means the actual load of
target cell is low, and vice versa.
In the hard-resource-unlimited list, cells are ranked according to soft resource, and rules
are as follows,
If target cell‟s available downlink power, uplink interference and code resource are all
bigger than their corresponding thresholds, (1-TCP_Load) > DlPwrThdCs/
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DlPwrThdR99Ps and (1-UlRtwpEffLoad) > UlLdThdCs/UlLdThdR99Ps and
(1-CodeLoadLev) > DlCdThdCs/ DlCdThdR99Ps, this cell‟s load is low; otherwise its
load is heavy. Base on this rule, source cell and target cells (in hard-resource-unlimited
list) are divided into two lists, low-load list and heavy-load list. Low-load list is in front of
heavy–load list. The LoadWeight of each cell in these two lists are calculated and cells
are ranked in descending order in the two lists separately. When LoadWeight is bigger,
the cell has more available load.
If all available resources of the source cell are bigger than the thresholds, source cell will
be put at the first place of the low-load list.
3.1.2 Strategy for HSPA
The load of the HSPA is evaluated by HSPA throughput or HSPA user number,
controlled by LdBalHspaStrCho. When LdBalHspaStrCho is set as “Multi-Factors
Combination Strategy”, balance based on HSPA throughput is used. When
LdBalHspaStrCho is set as “HSDPA User Number Strategy” and LdBalHsdNumSwch is
“on”, balance based on HSPA user number is used.
Balance based on HSPA user number is an independent function from balance based
on HSPA throughput, and it is applicable to all balance scenarios, such as RRC, RAB,
call holding and measurement based balancing.
3.1.2.1 Balance Based on HSPA Throughput
1. HSDPA
(a) HSDPA throughput per user (HsdThrouLoad)
cell in thenumber ser HSDPA
cell theoft throughpumaximumHSDPA rouLoad)user(HsdThper ughput HSDPA thro
u
Where,
HSDPA maximum throughput of the cell = min(HSDPA maximum throughput which is
provided by HSDPA available code in the cell, HSDPA maximum throughput which is
provided by HSDPA available power in the cell, HSDPA maximum throughput which is
provided by available transmission band in the cell)
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Where, the three factors are controlled by ldBalHsdCodFacCho, ldBalHsdPwrFacCho,
and ldBalHsdBandWidFacCho.
The definition of HSDPA equivalent user number is described as follows. Node B uses
SPI to schedule HSPA users. In this case, the user with a bigger SPI has a greater
chance to be scheduled and occupies more resources. Consequently, when calculating
cell‟s HS load, online users are equalized to user numbers according to the users‟
service and QoS. For example, the user with low QoS is equal to one basic user; while
the user with high QoS is equal to several users. As SPI is the BP of RNC which is sent
to Node B, a new parameter HspaEquHsUser is defined to indicate the equivalent user
numbers of each BP.
(i) HSDPA maximum throughput which is provided by HSDPA available code in the cell
HSDPA maximum throughput which is provided by HSDPA available code in the cell =
RateHspdschBitecupeiedRatsdpaCodeOcavailableH **61
Where,
ecupeiedRatsdpaCodeOcavailableH=
%100*16
pdsch)MaxNumofHs,128
16*)HSPDSCH128SF128((
OccupiedrForNonCodeNyumbeMin
MaxNumofHspdsch is the maximum HSPDSCH code in a cell
HspdschBitRate is the HS-PDSCH Bit Rate per one HS-PDSCH channel.
(ii) HSDPA maximum throughput which is provided by the HSDPA available power in the
cell
to ta ltxLcp ichc
CPICHtx
rH sAva ip o we
req
b
P
kN
E
P
P
NE
WR
,
k 2
1k
minmaxmin
0
,0
101
In which,
Load Balance Feature Guide
ZTE Confidential Proprietary 19
owerNonHSDSCHPhrNodeBSafeTP rHsAvaipowe
Ptx,total is the cell‟s valid load
is CpichEcN0, configured on the OMC
CPICHtxP
, refers to PCPICH transmit power (PcpichPwr)
k2
1k
minmaxmin
101
L
k
is , orthogonal factor
req
b
NE
0is the HSDPA Eb/N0 (HsdpaEbN0)
W = 3.84*10e+6
(iii) HSDPA maximum throughput which is provided by available transmission band in the
cell
HSDPA maximum throughput which is provided by available transmission band in the
cell=the maximum available transmission band from interface
(b) Throughput per user in the cell
%100*uSinHsdThro
adHsdThrouLordHsdThrouTh
Where,
SinHsdThrou is the maximum throughput for single user in the cell, SinHsdThrou=15 *
960kBps
If Throughput per user in the cell rdHsdThrouTh < DlLdHsThdHsd, it means that the
available HS throughput resource is limited and the HSDPA load is heavy.
(c) Coupling of HSDPA throughput and RTWP
c-cpich
0
E
N
Load Balance Feature Guide
ZTE Confidential Proprietary 20
If the uplink of the HSDPA is DCH, RTWP needs to be also considered.
RtwpRtwpRtwp
HSDPA
WeightoadThrdAvailableLoadAvailableL
WeightsdDlLdHsThdHrdHsdThrouThLoadWeight
*)(
*)(
Where,
RTWP is determined by UlLdBalPwrSwch. HSDPA throughput is determined by
LdBalHsdSwch.
Weight indicates the weight (corresponds to DlLdBalHsdWeight, UlLdBalPwrWeight
configured in the source cell) of each factor. RNC guarantees the sum of the two weights
is 1.
HsdThrouThrd and Availableload are the cell‟s available load. For source cell,
HsdThrouThrd plus ExtraDeltaHsdTrd, Availableload plus ExtraCDeltaTru
DlLdHsThdHsd is the available load balance threshold for HSDPA;
AvailableloadThrdRtwp, is UlLdThdCs/UlLdThdR99Ps
LoadWeight indicates the evaluation value. A large value means the actual load of the
target cell is low, and vice versa.
(d) Impact of DC-HSDPA
For DC-HSDPA, if HS-SCCH less is activated, load calculation is the same as that of a
single carrier because HS-SCCH is only used on primary carrier according to 3GPP. If
HS-SCCH less is not activated, HSDPA maximum throughput which is provided by
HSDPA available code in the cell and HSDPA maximum throughput which is provided by
HSDPA available power in the cell are equal to the sum of that of primary and secondary
carrier respectively. (Since transmission band is shared, the band information from the
interface is the available band of multi-cells.)
The candidate cell list includes all kinds of cells, dual carrier cell, single cell from dual
carrier cell and single cell. For example, if AB is dual carrier cell, A+B, B+A, A and B are
all in the candidate cell list. During load balancing, if UE has already tried to access A+B,
then later it will not try B+A, but will try to access A or B.
Load Balance Feature Guide
ZTE Confidential Proprietary 21
Criteria of primary serving cell selection:
HSPA throughput: When a multi-cell HSDPA (such as DC-HSDPA) includes the
same cells (such as AB and BA) and their LoadWeight are equal, the cell whose
load is lighter is chosen as the primary serving cell.
HSPA user number:
- When CresPara7 bit4 is off, and when a multi-cell HSDPA includes the same cells
and their LoadHSDPAAvaiUserNum are equal, the cell whose
LoadHSDPAAvaiUserNum (according to formula (1-1)) is bigger is chosen as the
primary serving cell. (Note, CurrentHSDPANum in formula (1-1) is “HSPA load
balance user number1”)
- When CresPara7 bit4 is on, and when a multi-cell HSDPA includes the same cells,
compare the load status of each cell with formula (2-1)
1) If cells are in different load lists (such as low-load list and heavy load list), the
cell whose LoadHSDPAAvaiUserNum (according to formula (1-1)) is bigger is
chosen as the primary serving cell.
2) If cells are in the same load list (such as low-load list or heavy load list), the
output is according to service-based/HSPA+ capability-based multi-carrier
strategy. When properties (service/ HSPA+ capability) of multi-cells (such as AB
and BA) are the same, the cell whose LoadHSDPAAvaiUserNum (according to
formula (1-1)) is bigger is chosen as the primary serving cell.
(Note, CurrentHSDPANum in formula (2-1) and (1-1) is “HSPA load balance user
number2”. For the definition of “HSPA load balance user number1” and “HSPA
load balance user number2,” refer to section 3.1.2.2)
If a multi-cell HSDPA is evaluated as low-load and the primary serving cell which is
source cell of this multi-cell HSDPA is also evaluated as low-load, the primary
serving cell will not be changed.
2. HSUPA
Load Balance Feature Guide
ZTE Confidential Proprietary 22
(a) HSUPA throughput per user (HsuThrouLoad)
cell in thenumber ser HSUPA
cell theoft throughpumaximumHSUPA rouLoad)user(HsuThper ughput HSUPA thro
u
Where,
HSUPA maximum throughput of the cell = min(HSUPA maximum throughput which is
provided by uplink interference in the cell, HSUPA maximum throughput which is
provided by available transmission band in the cell)
The definition of HSUPA equivalent user number is the same as that of HSDPA
equivalent user number.
(i) HSUPA maximum throughput which is provided by uplink interference in the cell
Based on , we have
)1(
to ta l
LI
IC
where, load factor
RWL iC
1
1)1(
then, HSUPA maximum throughput which is provided by uplink interference in the cell:
**)1*)1(
)1((
I
Ii
WR
total
I is the difference between the maximum RTWP in a cell and uplink effective load
is the uplink effective load
is the uplink activated factor, the value is 1
i is the uplink interference factor of neighboring cells to serving cell
I( ) I1
Ltotal
CdBm
totalI
Load Balance Feature Guide
ZTE Confidential Proprietary 23
η is 1 - N0 / Itotal , the value is 0.5
β is EbN0, uplink quality factor
W 3.84*10e+6
(ii) HSUPA maximum throughput which is provided by available transmission band in the
cell
HSUPA maximum throughput which is provided by available transmission band in the
cell = maximum available transmission band from the interface
(b) Throughput per user in the cell
%100*uSinHsuThro
adHsuThrouLordHsuThrouTh
Where,
SinHsdThrou is the maximum throughput for a single user in the cell, SinHsuThrou =
5.76Mbps
If Throughput per user in the cell rdHsuThrouTh < UlLdHsThdHsu, it means that the
available HS throughput resource is limited and the HSUPA load is heavy.
(c) When HSUPA is used, downlink is HSDPA. In this case, when evaluating the load of
HSUPA, HSDPA throughput also needs to be considered.
aH
Hsdpa
WeightsuUlLdHsThdHrdHsuThrouTh
WeightsdDlLdHsThdHrdHsdThrouThLoadWeight
sup*)(
*)(
Where,
HSDPA throughput is controlled by LdBalHsdSwch. HSUPA throughput is controlled by
LdBalHsuSwch.
Weight indicates the weight (corresponds to DlLdBalHsdWeight, UlLdBalHsuWeight
configured in the source cell) of each factor. RNC guarantees the sum of the two weights
is 1.
Load Balance Feature Guide
ZTE Confidential Proprietary 24
HsdThrouThrd and HsuThrouThrd are the cell‟s available load. For source cell,
HsuThrouThrd plus ExtraDeltaHsuTrd, HsdThrouThrd plus ExtraDeltaHsdTrd
DlLdHsThdHsd is the available load balance threshold for HSDPA, UlLdHsThdHsu is the
available load balance threshold for HSUPA
LoadWeight indicates the evaluation value. A larger value means lower actual load of
the target cell, and vice versa.
3. Rank of HSPA cells
(1) If the evaluated HSDPA cell‟s HsdThrouLoad> DlLdHsThdHsd
or(1-UlRtwpEffLoad>UlLdThdR99Ps; evaluated HSUPA cell‟s
HsUThrouLoad>UlLdHsThdHsu or HsdThrouLoad> DlLdHsThdHsd, this cell‟s load is
low; otherwise, it is heavy. Based on this rule, source cell and target cells are sorted into
two lists, low-load list and heavy-load list. Low-load list is in front of heavy–load list. The
LoadWeight of each cell in these two lists are calculated and cells are ranked in
descending order in the two lists separately. When LoadWeight is bigger, the cell has
more available load. If all available resources of a source cell are bigger than the
thresholds, the source cell will be put at the first place of low-load list.
(2) Multi-RAB of R99 and HSPA might occur during call holding procedure, the threshold
of R99 is used.
3.1.2.2 Balance Based on HSPA User Number
All cells in the low-load list and heavy-load list are ranked in descending order based on
LoadHSDPAAvaiUserNum. The first cell has the lightest load and has higher priority as
the target cell to be accessed. The formula of LoadHSDPAAvaiUserNum is as follows.
LoadHSDPAAvaiUserNum = (AcUserThrd – CurrentHSDPANum) – (AcUserThrd -
LdHsdUserNumThd_para)
Then,
(1) For single cell scenario:
Load Balance Feature Guide
ZTE Confidential Proprietary 25
LoadHSDPAAvaiUserNum = LdHsdUserNumThd_para –CurrentHSDPANum
Further, introducing DeltaHsdUsrNumTd_para, then:
LoadHSDPAAvaiUserNum = LdHsdUserNumThd_para – (CurrentHSDPANum -
DeltaHsdUsrNumTd_para) (1-1)
Where,
a) LdHsdUserNumThd_para: is each cell‟s LdHsdUserNumThd
b) CurrentHSDPANum: is “HSPA load balance user number1”
c) DeltaHsdUsrNumTd_para: if the cell is source cell, it is the cell‟s
DeltaHsdUsrNumTd; otherwise, it is 0. DeltaHsdUsrNumTd_para is offset of
source cell. Note, Source cell: the cell which a user will try to access to.
(2) For multi-cell (such as DC-HSDPA) scenario:
- when CresPara7 bit4 is off,
LoadHSDPAAvaiUserNum = (AcUserThrdPrimary – CurrentHSDPANumPrimary) –
(AcUserThrdPrimary - LdHsdUserNumThd_paraPrimary)
Then,
LoadHSDPAAvaiUserNum=LdHsdUserNumThd_paraPrimary–CurrentHSDPANumPrimary
Further,
LoadHSDPAAvaiUserNum=LdHsdUserNumThd_paraPrimary–(CurrentHSDPANumPrimary-
DeltaHsdUsrNumTd_paraPrimary) (1-2)
Where,
a) LdHsdUserNumThd_paraPrimary: is primary serving cell‟s LdHsdUserNumThd
Load Balance Feature Guide
ZTE Confidential Proprietary 26
b) CurrentHSDPANumPrimary: primary serving cell‟s “HSPA load balance user
number1”
c) DeltaHsdUsrNumTd_paraPrimary: if primary serving cell is the source cell, it is primary
serving cell‟s DeltaHsdUsrNumTd; otherwise, it is 0.
- when CresPara7 bit4 is on,
LoadHSDPAAvaiUserNum = (AcUserThrdPrimary–CurrentHSDPANumPrimary) +
(AcUserThrdSecd–CurrentHSDPANumSecd) - (AcUserThrdPrimary -
LdHsdUserNumThd_paraPrimary)
Then,
LoadHSDPAAvaiUserNum = LdHsdUserNumThd_paraPrimary –
CurrentHSDPANumPrimary + AcUserThrdSecd–CurrentHSDPANumSecd
Further,
LoadHSDPAAvaiUserNum = LdHsdUserNumThd_paraPrimary –
(CurrentHSDPANumPrimary- DeltaHsdUsrNumTd_paraPrimary) +
AcUserThrdSecd–(CurrentHSDPANumSecd-DeltaHsdUsrNumTd_paraSecd)
That is
LoadHSDPAAvaiUserNum = LdHsdUserNumThd_paraPrimary – CurrentHSDPANumPrimary
+ AcUserThrdSecd–CurrentHSDPANumSecd+ DeltaHsdUsrNumTd_paraPrimary+
DeltaHsdUsrNumTd_paraSecd (1-3)
Where,
a) LdHsdUserNumThd_paraPrimary; is the primary serving cell‟s LdHsdUserNumThd
b) CurrentHSDPANumPrimary, CurrentHSDPANumSecd: primary serving cell and
secondary serving cell‟s “HSPA load balance user number2”.
c) AcUserThrdSecd: secondary serving cell‟s HsdschTrafLimit
Load Balance Feature Guide
ZTE Confidential Proprietary 27
d) DeltaHsdUsrNumTd_paraPrimary and DeltaHsdUsrNumTd_paraSecd: if primary
serving cell is the source cell, they are the primary serving cell and secondary
serving cell‟s DeltaHsdUsrNumTd; otherwise, it is 0.
Note:
1) Considering application scenarios, HSPA user number is HSDPA (downlink is
HS-DSCH channel) user number.
2) When LdBalHsdNumSwch is on, CresPara7 bit4 is valid
3) LdBalHsdNumSwch and CresPara7 bit4 use source cell‟s switches
4) HSPA load balance user number1, the sum of this cell as primary serving cell,
secondary serving cell and single cell‟s user number
HSPA load balance user number2, the sum of this cell as primary serving cell and single
cell‟s user number
5) Cell‟s load status for a single cell: if LdHsdUserNumThd_para >CurrentHSDPANum,
(2-1) it is evaluated as low-load; otherwise, it is evaluated as heavy-load.
(CurrentHSDPANum: “HSPA load balance user number1”)
For multi-cell:
When CresPara7 bit4 is off, if LdHsdUserNumThd_paraPrimary >
CurrentHSDPANumPrimary, (2-2) it is evaluated as low-load; otherwise, it is evaluated
as heavy-load. (CurrentHSDPANum: “HSPA load balance user number1”)
When CresPara7 bit4 is on, if LdHsdUserNumThd_paraPrimary + AcUserThrdSecd >
CurrentHSDPANumPrimary+ CurrentHSDPANumSecd, (2-3) it is evaluated as low-load;
otherwise, it is evaluated as heavy-load. (CurrentHSDPANum: “HSPA load balance
user number2”)
If the source cell is multi-cell, (such as A is source cell, AB is multi-cell, A is primary
serving cell and B is secondary serving cell), then
Load Balance Feature Guide
ZTE Confidential Proprietary 28
If multi-cell (such as AB) is low-load
If primary serving cell (such as A) is low-load, then multi-cell is on the first place
in low-load list; otherwise, multi-cell is in the low-load list and all cells are
ranked in descending order according to LoadHSDPAAvaiUserNum.
If a multi-cell is heavy-load, then multi-cell is in heavy-load list.
Where, load status of the multi-cell uses formula (2-3); and load status of primary
serving cell uses formula (2-1)
3.2 Multi-mode System, Load Balance Strategy Among
Inter-system
Note: the strategy in this chapter is only used n multi-mode system.
Only R99 AMR is balanced from UMTS to GSM. Meanwhile, the inter-system balance
only occurs during RAB assignment, through Inter-RAT directed retry.
The 3G cell‟s quality must be evaluated before directed retry. If CpichEcN0 of the cell is
bigger than DREcNoQualThrd or CpichRSCP of the cell is bigger than DRRscpQualThrd
(if both CpichEcN0 and CpichRSCP are used, the two criteria must be satisfied), directed
retry will be implemented; otherwise, directed retry will not be used.
1. Inter-system Load balance strategy in a multi-mode system
As the load evaluation criterion of UMTS and GSM is different, in order to evaluate
UMTS and GSM cell‟s load, AMR12.2k is used as the criterion for both systems. The
more number of AMR12.2k can be accessed into a cell, which means the actual load of
target cell is lower, and vice versa.
(1) UMTS
(i) Downlink power
The power of a single AMR12.2k is calculated as follows.
Load Balance Feature Guide
ZTE Confidential Proprietary 29
to ta ltxL
cp ichc
CPICHtxreq
b
in ittx P
kN
E
P
PG
NE
P ,
k 2
1k
minmaxmin
0
,0
,
101
Where,
to tal,txP is the load of the current cell, which is 50% of the cell maximum transmission
power
0
p ichc
N
E
is CpichEcN0
CPICHtxP
, is the primary CPICH power
k2
1k
minmaxmin
101
L
k
is , whose value is 0.5
req
b
NE
0is the DlEbN0 of CS12.2k
PG is 25dB
The available number of users that can be accessed is calculated as follows,
inittxPcpUserAvailableT
,
TCP_Load%100
Note: TCP_load refers to 3.1.1 strategy for R99.
(ii) Uplink interference
The available number of users that can be accessed is calculated as follows
SingleI
oadUlRtwpEffLUlOverLdtwpUserAvailableR
Load Balance Feature Guide
ZTE Confidential Proprietary 30
Where,
UlOverLdis the Uplink overload upper limit
SingleI is the interference of a single AMR12.2k
UlRtwpEffLoad refers to 3.1.1 strategy for R99.
L
Lto ta lS ing le
C
CII
1
Where,
to talI comes from common measurement report of Node B, which is 50% of OriBckNoise
= 1 - N0 / Itotal, the value is 0.5
PG
iCL
1
1)1(
Where,
is the uplink activated factor
i is the uplink interference factor of neighboring cells to serving cell
β is EbN0, uplink quality factor, the value is UlEbN0 of CS12.2k
PG is 25dB
(iii) The available number of users can be accessed in a UMTS cell
twpUserAvailableRcpUserAvailableTMintUserAvailableU ,
(2) GSM
Load Balance Feature Guide
ZTE Confidential Proprietary 31
AvailableGsmUser = available CS channels
2. Rank of UMTS and GSM cells
In UMTS source cell, if (1-TCP_Load) > DlPwrThdCs4G and (1-UlRtwpEffLoad)>
UlLdThdCs4G, the load of source cell is low and it will be put at the first place of cell list.
Other cells will be ranked according to available number of users (AvailableUtUser or
AvailableGsmUser) in descending order. When the available number of users is bigger,
the load is low. Otherwise, all cells including source cell and target cells are ranked
according to available number of users.
3.3 Single/Multi-mode System, Load Balance Strategy
Inter-RNC
Standard Iur in 3GPP is used as the interface between multi-mode UMTS and standard
UMTS, and among multi-mode UMTS. Moreover, load balance only occurs during RAB
assignment.
Due to incomplete load information on Iur, load balance strategy between two RNCs is
simplified as follows,
If the selected best cell is under DRNC during initial RRC procedure, it will not
perform load-based multi-carrier interoperation, service-based multi-carrier
interoperation and HSPA+ capability-based multi-carrier interoperation later.
If there are DRNC cells in the candidate cell list which consists of neighboring cells
with “Overlap” or “Covers”(ShareCover) relationship, those DRNC cells will be put
at the first place of the heavy–load list.
3.4 Single/Multi-mode System, Load Balance Strategy
Among Inter-system
Standard Iur-g in 3GPP is used as the interface between multi-mode UMTS and
standard GSM/multi-mode GSM. Moreover, load balance only occurs during RAB
Load Balance Feature Guide
ZTE Confidential Proprietary 32
assignment.
The strategy in this chapter is almost the same as that in chapter 3.2. The only difference
is that AvailableGsmUser cannot be obtained from Iur-g, so the available number of
users is calculated based on the load information from Iur-g. The details are as follows,
If RT load information is reported on Iur-g, the available number of users is
calculated as AvailableGsmUser = (100%-RT)*GsmCelCariNum*8, because one
GSM carrier supports 8 AMR12.2k. In which, GsmCelCariNum is defined on the
OMC and RT = Max (uplink RT, downlink RT).
If RT load information is not reported on Iur-g, the available number of user is
calculated as AvailableGsmUser=50%*GsmCelCariNum*8.
3.5 Load Balance Strategy When Multi System Exist
When multiple systems exist, for example multi-mode system intra-UMTS, multi-mode
inter-system, between multi-mode UMTS and single-mode UMTS, or between
multi-mode GSM and single-mode GSM, there are several application scenarios.
Generally, more load information can be exchanged on multi-mode system‟s internal
interface than standard 3GPP interface. Therefore, load balance in a multi-mode
intra–RNC system has higher priority, but in some special cases it is preferred that UE is
balanced to GSM cells in multi-mode system rather than UMTS cells.
A multi-mode intra–UMTS system might also perform HSPA+ capability-based
multi-carrier interoperation and service-based multi-carrier interoperation later, but other
systems do not have these two interoperations. The rules of cell ranking are as follows.
(1) Systems are ranked according to the equivalent number of users in descending order.
(2) In each system, cells are separately ranked according to the rules in chapter 3.1~3.4.
(3) Define UtraUserNumOff, CoGsmUserNumOff and GsmUserNumOff to indicate the offset of
each system. That is to say, when comparing the available number of users of each
system, the corresponding system needs to add this offset.
When multiple systems exist, a UMTS system needs to supply its load information to
Load Balance Feature Guide
ZTE Confidential Proprietary 33
other systems. Details are as follows,
(1) Define HSDPA User Number Low Threshold (DPAUNumLowThd) on the OMC. When
a cell‟s number of HSDPA users is less than this parameter, this cell‟s HSDPA user load
status is low, which can also apply to HSUPA User Number Low Threshold
(UPAUNumLowThd)/ MBMS User Number Low Threshold (MBMSUNumLowThd) /
Signal User Number Low Threshold (SigUNumLowThd)/ Code Load Low Threshold
(CodeLoadLowThd)/ CE Load Low Threshold (CELoadLowThd). Meanwhile, define
HSDPA User Number Middle Threshold (DPAUNumMidThd) on OMC. When a cell‟s
number of HSDPA users is bigger than DPAUNumLowThd but less than
DPAUNumMidThd, this cell‟s HSDPA user load status is medium; while if this cell‟s
number of HSDPA users is bigger than DPAUNumMidThd, this cell‟s HSDPA user load
status is high. This can also apply to HSUPA User Number Middle Threshold
(UPAUNumMidThd)/ MBMS User Number Middle Threshold (MBMSUNumMidThd)/
Signal User Number Middle Threshold (SigUNumMidThd)/ Code Load Middle Threshold
(CodeLoadMidThd)/ CE Load Middle Threshold (CELoadMidThd).
(2) For TCP and RTWP, when a cell‟s TCP effective load is smaller than TCP Load Low
Threshold (TCPLoadLowThd), this cell‟s TCP load status is low. When a cell‟s TCP
effective load is bigger than TCPLoadLowThd but smaller than TCP Load Middle
Threshold (TCPLoadMidThd), this cell‟s TCP load status is medium. When a cell‟s TCP
effective load is bigger than TCPLoadMidThd but smaller than TCP Load High Threshold
(TCPLoadHighThd), this cell‟s TCP load status is high. When a cell‟s TCP effective load
is bigger than TCPLoadHighThd, this cell‟s TCP load status is overload. This can also
apply to RTWP and the thresholds are RtwpLoadLowThd, RtwpLoadMidThd,
RtwpLoadHighThd.
3.6 Load-based Multi-carrier Interoperation in Initial
RRC procedure
The load-based multi-carrier interoperation in the initial RRC procedure is only applied to
“1: Single/Multi-mode System, Load Balance Strategy Intra-RNC”. If InitRrcLBSw is set
to ON, a cell with the lowest load will be selected for access according to “1:
Single/Multi-mode System, Load Balance Strategy Intra-RNC”.
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ZTE Confidential Proprietary 34
During the initial RRC procedure, when signaling sets up on DCH and it is PS service
(refer to chapter 4.1) and UE‟s version is R5 or later, if RrcHsLdBaOnDchSw is “on”, the
strategy of HSDPA load balancing is used; otherwise, R99‟s is used.
Note: In the initial RRC procedure, the specific services and some capabilities of the UE
are not known. To avoid the balance failure due to balancing UE to the band that the UE
does not support, the neighboring cell whose frequency band is different from the current
serving cell will not be taken into account as the target cell of the load balancing.
3.7 Load-based Multi-carrier Interoperation in RAB
assignment
The load-based multi-carrier interoperation during RAB assignment can be applied to the
four scenarios above. If RabAssLBSw is set to ON, a cell with the lowest load will be
selected for access. For more details, refer to chapter 3.1 to 3.4.
For CS Service, CsBalSwch should be also indicated whether the balance function is
open for CS service during RAB assignment procedure. If CsBalSwch switch is set to
„Closed‟, the load balance will not be triggered for CS service, and vice versa.
After the introduction of HSDPA and HSUPA, the cells can be categorized into multiple
types:
1) Cells supporting HSUPA and HSDPA.
2) Cells supporting HSUPA, HSDPA and DCH.
3) Cells supporting HSDPA and DCH.
4) Cells supporting HSDPA only.
5) Cells which do not support HSUPA and HSDPA. There are also UMTS2100 and
UMTS 900 cells of different bands. The UE provides different support to these cells.
Therefore, in the load-based multi-carrier interoperation during RAB assignment, the
service properties and UE capabilities should be taken into consideration to select the
target cell.
Load Balance Feature Guide
ZTE Confidential Proprietary 35
The specific principles are as follows:
(1) Combine the target cell of UE for access/handover and its neighboring cells which are
with “Overlap” or “Covers” (ShareCover) relationship into a target cell Set;
(2) Select a set (named as Set1) of cells from step (1) whose band is supported by the
UE ;
(3) Select a set (named as Set2) of cells from Set1 in step (2) which the UE provided
service support;
(4) Select the lowest load cell as the final target cell for access/handover in Set2.
See services and target cell types which can carry the services in the following table:
Table 3-1 Services and target cell types which can carry the services
Service Type DCH/DCH HS-DSCH/DCH HS-DSCH/E-DCH
Target cell types
which can carry
the services
Cells do not support
HSUPA and HSDPA
Cells support
HSDPA and DCH
Cells support
HSUPA, HSDPA,
and DCH
Cells support
HSDPA and DCH
Cells support
HSUPA, HSDPA,
and DCH
Cells support
HSUPA and HSDPA
Cells support
HSUPA, HSDPA,
and DCH
That is to say, the cell whose service type is not included in the above table will be
considered as an unsupported cell, and excluded out of the cell list.
3.8 Load-Based Multi-carrier Interoperation in Call
holding procedure
In state transition from non-CELL_DCH to CELL_DCH, channel transition, if
CallHoldLBSw is set to ON, the judgment of load-based multi-carrier interoperation
during call holding procedure is performed. Its handling procedure is the same as that of
the load-based multi-carrier interoperation during RAB assignment, but load-Based
multi-carrier interoperation in call holding procedure is only applied to “1:
Load Balance Feature Guide
ZTE Confidential Proprietary 36
Single/Multi-mode System, Load Balance Strategy Intra-RNC”.
3.9 Load-Based Multi-carrier Interoperation in
Handover/Call re-establishment procedure
During handover, relocation from other system or RNC to local RNC, call
re-establishment triggered by CELL UPDATE, if HoCalRestblLBSwch is set to ON,
load-based multi-carrier interoperation in handover/call re-establishment procedure is
performed. Its handling procedure is the same as that of load-based multi-carrier
interoperation during call holding procedure.
4 Service-based Multi-carrier
Interoperation
Notes: the multi-carrier interoperation in this chapter is only used to scenario “1:
single/multi-mode system, Intra-RNC”.
The serving cells can be categorized by service type (HspaSptMeth) into five types:
1) Cells supporting HSUPA and HSDPA;
2) Cells supporting HSUPA, HSDPA and DCH;
3) Cells supporting HSDPA and DCH;
4) Cells supporting HSDPA only;
5) Cells which do not support HSUPA and HSDPA.
And by frequency-band, the cells can be divided into UMTS900, UMTS2100 and so on.
The services carried by the cells may vary according to cell types. For example, the cells
which do not support HSUPA and HSDPA mainly carry voice services, while cells
supporting HSDPA and DCH mainly carry data services. As a result, the parameter
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“CsTrafPrefInd/r99PsTrafPrefInd/hsTrafPrefInd” are defined for each cell to instruct
which type of service is preferred for that cell. The operator can set the parameter flexibly
to satisfy the requirements in different scenarios.
Service-based multi-carrier interoperation selects a target cell preferably during Initial
RRC procedure, RAB assignment, and call holding procedure, rather than triggering the
handover actively. That is, when selecting a target cell during Initial RRC procedure, RAB
assignment, and call holding procedure, RNC will select a proper cell as the target cell
for access or handover based on specific service originated by the user equipment (UE).
Its application scenarios are classified into three types:
Initial RRC procedure: involving Initial RRC procedure.
RAB assignment: involving the first RAB assignment.
Call holding procedure: involving handover, relocation from other system or RNC to
local RNC, call re-establishment triggered by CELL UPDATE, state transition from
non-CELL_DCH to CELL_DCH.
In the three scenarios, related functions are controlled by three switches configured by
OMC: InitRrcSBSw, RabAssSBSw, and CallHoldSBSw.
4.1 Service-based Multi-carrier Interoperation in Initial
RRC procedure
In the Initial RRC procedure, if InitRrcSBSw is set to ON, and the cell where the UE
currently resides has inter-frequency neighboring cells which are with “Overlap” or
“Covers” (ShareCover) relationship, the most suitable cell to be accessed is selected
from the current cell and the neighboring cells based on the Establishment cause of RRC
request, UE supporting status, and cell properties
(CsTrafPrefInd/r99PsTrafPrefInd/hsTrafPrefInd, HspaSptMeth).
Detailed preference rules of the target cell are as follows:
1. RRC connection request for CS service
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Table 4-1 Candidate cell list selection for CS service
DCH DL: HS-DSCH / UL:
DCH
DL: HS-DSCH / UL:
E-DCH
or DL: DCH / UL:
E-DCH
R4 UE Cells do not support
HSUPA and HSDPA;
Cells support
HSDPA and DCH;
Cells support HSUPA,
HSDPA, and DCH;
/
/
R5 UE Cells do not support
HSUPA and HSDPA;
Cells support
HSDPA and DCH;
Cells support HSUPA,
HSDPA, and DCH;
/ /
R6 UE or
later
If call type is ”speech” and
UE supports CS over
hspa, then Cells support
HSUPA and HSDPA;
Cells support HSUPA,
HSDPA, and DCH;
Otherwise,
Cells do not support
HSUPA and HSDPA;
Cells support
HSDPA and DCH;
Cells support HSUPA,
HSDPA, and DCH;
If call type
is ”speech” and UE
supports CS over
hspa, then
Cells support
HSUPA and
HSDPA;
Cells support
HSUPA, HSDPA,
and DCH;
Otherwise,
Cells support
HSDPA and DCH;
Cells support
HSUPA, HSDPA,
and DCH;
If call type
is ”speech” and UE
supports CS over
hspa, then
Cells support
HSUPA and
HSDPA;
Cells support
HSUPA, HSDPA,
and DCH;
Otherwise,
Cells support
HSUPA, HSDPA,
and DCH;
When one of the criteria in the candidate cell list above is satisfied, if initial RRC
procedure load balance is on, UEs access the CS preferred cell from cells in chapter 3.2;
if initial RRC procedure load balance is off, UEs access the CS preferred cell from the
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candidate cell list. When none of the criteria in the candidate cell list above is satisfied,
UEs access the current serving cell.
Establishment cause of Originating Conversational Call, Terminating Conversational Call,
Inter-RAT Cell Reselection and Emergency Call are considered as CS service.
2. RRC connection request for PS service
Table 4-2 Candidate cell list selection for PS service
DCH DL: HS-DSCH /
UL: DCH
DL: HS-DSCH /
UL: E-DCH or DL:
DCH / UL: E-DCH
R4 UE Cells do not support
HSUPA and
HSDPA;
Cells support
HSDPA and DCH;
Cells support
HSUPA, HSDPA,
and DCH;
/ /
R5 UE Cells support
HSDPA only;
Cells support
HSDPA and DCH;
Cells support
HSUPA and HSDPA
Cells support
HSUPA, HSDPA,
and DCH;
/ /
R6 UE or later Cells support
HSDPA only;
Cells support
HSDPA and DCH;
Cells support
HSUPA and HSDPA
Cells support
HSUPA, HSDPA,
Cells support
HSDPA only;
Cells support
HSDPA and DCH;
Cells support
HSUPA and HSDPA
Cells support
HSUPA, HSDPA,
Cells support
HSUPA and HSDPA
Cells support
HSUPA, HSDPA,
and DCH;
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DCH DL: HS-DSCH /
UL: DCH
DL: HS-DSCH /
UL: E-DCH or DL:
DCH / UL: E-DCH
and DCH; and DCH;
When one of the criteria in the candidate cell list above is satisfied, if initial RRC
procedure load balance is on, the target cell is selected from the cells in chapter 3.2; if
initial RRC procedure load balance is off, the target cell is selected from the candidate
cell list. Moreover, the target cell also needs to satisfy the criteria below,
R4 UE, UEs access the R99 PS Preferred cell
R5, R6 or later, UEs access the HS PS Preferred cell
When none of the criteria in the candidate cell list above is satisfied, UEs access the
current serving cell.
Establishment cause of Originating Streaming Call, Originating Interactive Call,
Originating Background Call, Terminating Streaming Call, Terminating Interactive Call,
Terminating Background Call, Originating High Priority Signalling, Terminating High
Priority Signalling, Call Re-establishment, Inter-RAT Cell Change Order, Originating
Subscribed Traffic Call are considered as PS service.
3. RRC connection request for other services
UEs access the current service cell.
Establishment cause of Registration, MBMS reception, MBMS ptp RB request, Detach,
Terminating - cause unknown are considered as other services.
4. When the establishment cause in RRC connection request is Originating Low Priority
Signalling or Terminating Low Priority Signalling, the two causes are classified by
CRESPARA1. If CRESPARA1 is 0, the two causes are considered as PS services; if
CRESPARA1 is 1, the two causes are considered as CS services; if CRESPARA1 is 2,
the two causes are considered as other services; if CRESPARA1 is greater than 2, the
value of CRESPARA1 is considered as 0.
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4.2 Service-based Multi-carrier Interoperation in RAB
Assignment
During RAB assignment, if RabAssSBS is set to ON, the system will perform the
judgment of the service-based multi-carrier interoperation during RAB assignment. After
the introduction of HSDPA and HSUPA, the cells (HspaSptMeth) can be categorized into
multiple types: 1) Cells supporting HSUPA and HSDPA. 2) Cells supporting HSUPA,
HSDPA and DCH. 3) Cells supporting HSDPA and DCH. 4) Cells supporting HSDPA only.
5) Cells which do not support HSUPA and HSDPA. Based on band, the cells can be
divided into UMTS900 and UMTS1800. The supporting capabilities of a UE vary by the
type of the cell. Consequently, the sorting and selection of the target cell should be
based on the UE capabilities, current established services, and the Prefer property of
each cell. The detailed procedure is as follows:
(1) Combine the current cell where the UE resides and its neighboring cells which have
“Overlap” or “ Covers”(ShareCover) relationship with a target cell set (named Set);
(2) Exclude the cells whose bands are not supported by the UE and the cells which are
not supported by the current service originated by the UE from the Set in step (1). The
remaining cells form a target set named Set1. The cell types which are supported by the
current services of UE are as follows:
Table 4-3 Table of Cell Types Supported by Current Services of UE
Service Type DCH/DCH HS-DSCH/DCH HS-DSCH/E-DCH
Target cell types
which can carry
the services
Cells which do not
support HSUPA and
HSDPA;
Cells supporting
HSDPA and DCH;
Cells supporting
HSUPA, HSDPA,
and DCH;
Cells supporting
HSDPA and DCH;
Cells supporting
HSUPA, HSDPA,
and DCH;
Cells supporting
HSUPA and
HSDPA;
Cells supporting
HSUPA, HSDPA,
and DCH;
Specifically, the cell whose service type is not included in the above table will be
considered as an unsupported cell, and excluded out of the cell list.
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Notes: When service is reconfigured and the current cell does not support the service
type originated by the UE, the UE will choose another cell to access because the current
cell is excluded out of the cell list and this process is called blind handover. In order to
increase the success rate of blind handover, the quality (RSCP/EcN0) of current cell is
evaluated. Details are as follows:
According to saved Cpich EcN0 and Cpich RSCP of best cell in the active set, if current
cell‟s Cpich EcN0>EcNoQualThrd and Cpich Rscp> RscpQualThrd, it goes to step (3);
otherwise, UE accesses the current cell. If non Cpich EcN0 or Cpich RSCP is saved,
there is no need to carry out the evaluation of the current cell‟s quality.
(3) Cells in Set1 in step (2) will be sorted according to specific service types and the
Prefer property of cells (CsTrafPrefInd/r99PsTrafPrefInd/hsTrafPrefInd). See below table.
Table 4-4 Table of Sequence of Cells of Services
Sequence of Cells
CS service Cells that only CS preferred is configured
The rest cells that CS preferred configuration is included
Cells that CS preferred is not configured
R99 PS service Cells that only R99 PS preferred is configured
The rest cells that R99 PS preferred configuration is included
Cells that R99 PS preferred is not configured
HS PS service Cells that only HS PS preferred is configured
The rest cells that HS PS preferred configuration is included
Cells that HS PS preferred is not configured
CS + R99 PS
services
Cells that only CS and R99 PS preferred are configured
The rest cells that CS and R99 PS preferred configuration are
included
Cells that CS and R99 PS preferred are not configured
CS + HS PS
services
Cells that only CS and HS PS preferred are configured
The rest cells that CS and HS PS preferred configuration are
included
Cells that CS and HS PS preferred are not configured
(4) If the HCS function is introduced for cells, the cells should be sorted based on the
HCS priorities of target cells in descending order in the sorting in step (3). (The HCS
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priority ranges from 0 to 7. 0 is the lowest priority with relatively wide coverage, while 7 is
the highest priority with relatively small coverage). That is to say, sort the listed cells
based on the HCS properties in the precondition of meeting the preferred property.
Based on the deletion and preference sorting procedures on the listed target cells in the
above steps, select the first cell in the list as the target cell for access or handover.
When the type of a cell is R99+R5+R6 or R99+R5, and only HS PS preferred is
configured, PS service is released first for R99 CS+PS service, CsHo4MulRabSwch is
used to control whether the UE is handed over to a cell which is overlapped or co-located,
R99 service available and not only HS PS preferred.
One frequency covers the whole area, and another frequency only covers some
hotspots. In order to avoid CS call drop increasing if CS is set up on a hotspot and
hands over at the boundary, PS+CS service balance strategy is introduced. The
details are as follows. This function is controlled by MulRabBlSwch and
RabAssSBSw, and is independent with CsBalSwch. When UE initials first RAB R99
PS/HS PS and then initials second RAB CS on cell without CS prefer, if
MulRabBlSwch is on and the current cell has overlap / Covers neighboring cells with
CS prefer, the target cell is selected according to multi-RAB service balance strategy;
otherwise, second RAB CS is set up on the current cell.
4.3 Service-based Multi-carrier Interoperation in Call
holding procedure
During state transition from non-CELL_DCH to CELL_DCH, channel transition, if
CallHoldLBSw is set to ON, the judgment of service-based multi-carrier interoperation in
call holding procedure is performed. Its handling procedure is the same as that of the
service-based multi-carrier interoperation during RAB assignment.
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4.4 Service-based Multi-carrier Interoperation in
Handover/Call re-establishment procedure
During handover, relocation from other system or RNC to local RNC, call
re-establishment triggered by CELL UPDATE, if HoCalRestblSBSwch is set to ON, the
judgment of service-based multi-carrier interoperation is performed. Its handling
procedure is the same as that of the service-based multi-carrier interoperation during call
holding procedure.
5 HSPA+ Feature Related Balance
5.1 DC Traffic Redirection
Notes: the multi-carrier interoperation in this chapter is only used to 1: single/multi-mode
system, Intra-RNC.
This feature is controlled by DcRedirectStaSw.
If the value of DcRedirectStaSw is “1:On”, PS Service is requested by the UE with DC
capability from non-DC cell which has an available DC capability inter-frequency
neighbor cell, and the quality value of the serving cell reported by IE “Measured results
on RACH” in RRC CONNECTION REQUEST is better than DulCarBalRscpThd or
DulCarBalEcNoThd (if the report is P-CPICH RSCP, then it is compared with
DulCarBalRscpThd; if the report is P-CPICH Ec/N0, then it is compared with
DulCarBalEcNoThd), then RNC will send RRC CONNECTION REJECT message with
the DC carrier information in IE “Redirection info” to the UE. Otherwise, RRC SETUP will
be the routine process.
Notes: when PS service is indicated by IE “establishment cause” in RRC CONNECTION
REQUEST, refer to “4.1 Service-based Multi-carrier Interoperation in Initial RRC
procedure” for detailed information.
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5.2 HSPA+ capability-based Multi-carrier Interoperation
5.2.1 HSPA+ capability-based Multi-carrier Interoperation in Initial RRC
procedure
During RRC CONNECTION SETUP Stage, only DC HSDPA capability can be known,
and other HSPA+ feature capabilities are unknown, so only DC HSDPA capability is
taken into account for balancing during the RRC CONNECTION SETUP stage. This
feature is controlled by RrcDualCarrSw. If PS service is request by DC Capability UE and
the value of RrcDualCarrSw is “1:On” but RRC CONNECTION signaling is configured on
the DCH, then RRC CONNECTION SETUP is preferred to be set up on the DC capability
cell (if current serving cell supports DC, the UE accesses to current cell; if the current
serving cell does not support DC but it has an available DC capability inter-frequency
neighbor cell with “Overlap” or “ Covers” (ShareCover), UE accesses this neighbor cell);
otherwise, RRC CONNECTION SETUP is to set up on the non- DC capability cell.
Notes: when PS service is indicated by IE “establishment cause” in RRC CONNECTION
REQUEST, refer to “4.1 Service-based Multi-carrier Interoperation in Initial RRC
procedure” for detailed information.
5.2.2 HSPA+ capability-based Multi-carrier Interoperation in RAB
Assignment
During RAB Assignment, if RABHSPAPLUBALSW is “on”, the system will perform the
judgment of HSPA+ capability-based multi-carrier interoperation.
HSPA+ includes many capabilities (such as HS-SCCH less, DC HSDPA, 64QAM, MIMO,
and MIMO+64QAM). HspaPlusCapInd indicates which capability works and indicates the
priority of each HSPA+ capability. When judging whether the target cell supports HSPA+
capabilities, each capability is evaluated individually. For example, HS-SCCH less and
MIMO cannot be used simultaneously in 3GPP release 8. When MIMO is used,
HS-SCCH less cannot be used which is guaranteed by configuring MIMO and HS-SCCH
less with different priorities.
If the UE supports a certain HSPA+ capability and this HSPA+ feature will be taken into
account during load balancing, the cell (including the current serving cell and
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inter-frequency neighbor cell with “Overlap” or “Covers” (ShareCover)) with this HSPA+
capability will be preferred to be selected as the target cell. Correspondingly, if the UE
does not support some HSPA+ capability, the cell (including the current serving cell and
inter-frequency neighbor cell with “Overlap” or “Covers” (ShareCover)) without this HSPA+
capability will be preferred to be selected as the target cell in order to save resources for
the UE with this HSPA+ capability.
5.2.3 HSPA+ capability-based Multi-carrier Interoperation in Call holding
procedure
During state transition from non-CELL_DCH to CELL_DCH, channel transition, if
HOLDHSPAPLUBALSW is set to ON, the judgment of HSPA+ capability-based
multi-carrier interoperation in call holding procedure is performed. Its handling procedure
is the same as that of the HSPA+ capability-based multi-carrier interoperation in RAB
assignment.
5.2.4 HSPA+ capability-based Multi-carrier Interoperation in Handover/Call
re-establishment procedure
During handover, relocation from other system or RNC to local RNC, call
re-establishment triggered by CELL UPDATE, if HoHspaPlusBalSw is set to ON,
HSPA+ capability-based multi-carrier interoperation in handover/call re-establishment
procedure is performed. Its handling procedure is the same as that of the HSPA+
capability-based multi-carrier interoperation in call holding procedure.
6 Coupling of Load-based, HSPA+
capability-based and Service-based
Multi-carrier Interoperations
Handover is not automatically triggered but only cell reordering is performed when
load-based balance strategy, HSPA+ capability-based balance strategy and
service-based balance strategy are applied in the initial access phase and the call
reservation phase. Because the system load greatly affects the system stability,
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load-based balance strategy has a higher priority than HSPA+ capability-based balance
strategy and service-based balance strategy, specifically, load-based cell reordering is
prior to HSPA+ capability-based and service-based cell reordering. For example, first the
cells are reordered in the sequence from lower to higher loads according to the
"load-based multi-carrier interoperation" strategy, and are classified into a low-load cell
group and a high-load cell group. Then the two groups of cells are reordered by the
HSPA+ capability and service category, and the cell Prefer attribute
(CsTrafPrefInd/r99PsTrafPrefInd/hsTrafPrefInd) according to “HSPA+ capability-based
multi-carrier interoperation” and "service-based multi-carrier interoperation" strategy.
7 Measurement -based Multi-carrier
Interoperation
Measurement-based multi-carrier interoperation is used during RAB assignment process
and controlled by RabMeaBalStaSwch. This function is valid only for intra-RNC cells (an
RNC cannot get load information of cells in other RNCs).
When RabMeaBalStaSwch is off, the procedures of load-based, service-based and
HSPA+ capability-based multi-carrier interoperation in previous chapters are not
changed. They only work on neighboring cells with “Overlap” or “ Covers”(ShareCover)
relationship.
When RabMeaBalStaSwch is on, and load-based, service-based or HSPA+
capability-based multi-carrier interoperation during RAB assignment is on, compressed
mode is active and inter-frequency measurement is sent to UE for neighboring cells with
“Neighbor” or “Contained in”(ShareCover). The operation for neighboring cells with
“Overlap” or “Covers” (ShareCover) is further depended on CoverMeaBalSwch. When
CoverMeaBalSwch is on, compressed mode is active and inter-frequency measurement
is sent to the UE for neighboring cells with “Overlap” or “Covers” (ShareCover);
otherwise, the operation is the same as those in previous chapters.
In order to avoid a lot of users to activate compressed mode, SimCompUserNum is used
to control the number of users with compressed mode at the same time (only for
measurement-based multi-carrier interoperation). If the number of users is greater or
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equal to SimCompUserNum, compressed mode is not active; otherwise, compressed
mode is active.
When compressed mode is active, MeasBalTimer starts. When MeasBalTimer is on, if
inter-frequency handover switch or iforrathoswch forbids inter-frequency handover and
RNC receives inter-RAT event 2D or Uplink Transmit Power Based / Downlink Transmit
Power Based / Uplink BLER Based handover is triggered (refer to <ZTE UMTS
Handover Control Feature Guide>), MeasBalTimer stops. If the timer stops or expires,
compressed mode is de-active.
After compressed mode is active, 1) if NonIntraMeasQuan is EcN0 or RSCP, the
corresponding event 2C is sent to the UE; 2) if NonIntraMeasQuan is EcN0 and RSCP,
event 2C of Cpich RSCP is sent to the UE.
When RNC receives event 2C, the reported inter-frequency neighboring cells which do
not include cells controlled by other RNCs, and source cell compose a candidate cell list.
These cells queue according to load-based, service-based or HSPA+ capability-based
multi-carrier interoperation during RAB assignment (here, CsBalSwch is not considered).
If the first one is a source cell, compressed mode is de-active and MeasBalTimer stops;
Otherwise, the UE hands over the first cell.
8 Strategy of Balance Failure
Parameter BalFailOpSwch controls the function that RB can be tried to be set up on the
source cell if balancing failed. When this parameter is “on”, if the UE sends a Uu Failure
response during any balance procedure except initial RRC procedure and relocation, the
RNC tries to set up RB on the source cell.
9 UTRAN -> EUTRAN Service Balance
This function is controlled by U2EBalSwch. Currently, as EUTRAN only carries PS
service, only PS is considered in UTRAN to EUTRAN service balance. When
U2EBalSwch is set as “1”, if the UE sends a RRC connection request to the RNC and the
service is PS, and IE “Pre-redirection info” is present and indicates EUTRA support, the
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RNC sends RRC Connection Reject to the UE and EUTRA frequencies are filled in IE
“Inter-RAT info” contained in IE Redirection Info.
10 Parameters and Configurations
10.1 Parameter List
Abbreviated Name Parameter Name
InitRrcLBSw Load Balance Switch of Initial RRC Procedure
RabAssLBSw Load Balance Switch of RAB Assignment Procedure
CallHoldLBSw Load Balance Switch of Call holding Procedure
DlLdBalPwrSwch Load Balance Switch for Downlink Power
UlLdBalPwrSwch Load Balance Switch for Uplink Interference
LdBalCdSwch Load balance switch for code
LdBalHsdSwch Load Balance Switch for HSDPA Throughput
LdBalBwSwch Load Balance Switch for Bandwidth
DlLdBalPwrWeight Downlink Power weight for load balance
UlLdBalPwrWeight Uplink Interference Weight for Load Balance
LdBalCdWeight Code weight for load balance
DlLdBalHsdWeight HSDPA Throughput Weight for Load Balance
UlLdBalHsuWeight HSUPA Throughput Weight for Load Balance
DlPwrThdCs UTRAN Downlink Available Load Balance Threshold
(Power) for CS
DlPwrThdR99Ps UTRAN Downlink Available Load Balance Threshold
(Power) for R99 PS
UlLdThdCs UTRAN Uplink Available Load Balance Threshold
(Interference) for CS
UlLdThdR99Ps UTRAN Uplink Available Load Balance Threshold
(Interference) for R99 PS
DlCdThdCs UTRAN Downlink Available Load Balance Threshold
(Code) for CS
DlCdThdR99Ps UTRAN Downlink Available Load Balance Threshold
(Code) for R99 PS
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Abbreviated Name Parameter Name
DlLdHsThdHsd UTRAN Downlink Available Load Balance Threshold
(HSDPA Throughput) for HSDPA
UlLdHsThdHsu UTRAN Uplink Available Load Balance Threshold (HSUPA
Throughput) for HSUPA
DlPwrThdCs4G Inter-RAT Downlink Available Load Balance Threshold
(Power) for CS
UlLdThdCs4G Inter-system Uplink Available Load Balance Threshold
(Interference) for CS
ExtraCDeltaTrd Permitted Payload Difference Downlink Available Load
Threshold in Inter-frequency Cells (Power)
ExtraCDeltaTru Permitted Payload Difference Uplink Available Load
Threshold in Inter-frequency Cells (Interference)
ExtraCDeltaCdTrd Permitted Payload Difference Downlink Available Load
Threshold in Inter-frequency Cells (Code)
ExtraDeltaHsdTrd Permitted Payload Difference Downlink Available Load
Threshold in Inter-frequency Cells (HSDPA Throughout)
ExtraDeltaHsuTrd Permitted Payload Difference Available Load Threshold in
Inter-frequency Cells (HSUPA Throughput)
HspaEquHsUser Equivalent HSPA Users
GsmCelCariNum GSM Cell‟s Carrier Number
UtraUserNumOff User Number Offset of UTRAN for Balance
CoGsmUserNumOff User Number Offset of GSM in Multi-Mode System for
Balance
GsmUserNumOff User Number Offset of GSM for Balance
TCPLoadLowThd TCP Load Low Threshold
TCPLoadMidThd TCP Load Middle Threshold
TCPLoadHighThd TCP Load High Threshold
RtwpLoadLowThd RTWP Load Low Threshold
RtwpLoadMidThd RTWP Load Middle Threshold
RtwpLoadHighThd RTWP Load High Threshold
DPAUNumLowThd HSDPA User Number Low Threshold
DPAUNumMidThd HSDPA User Number Middle Threshold
UPAUNumLowThd HSUPA User Number Low Threshold
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Abbreviated Name Parameter Name
UPAUNumMidThd HSUPA User Number Middle Threshold
MBMSUNumLowThd MBMS User Number Low Threshold
MBMSUNumMidThd MBMS User Number Middle Threshold
SigUNumLowThd Signal User Number Low Threshold
SigUNumMidThd Signal User Number Middle Threshold
CodeLoadLowThd Code Load Low Threshold
CodeLoadMidThd Code Load Middle Threshold
CELoadLowThd CE Load Low Threshold
CELoadMidThd CE Load Middle Threshold
LoadBalanceScene Load Balance Scene
InitRrcSBSw Service Balance Switch of Initial RRC Procedure
RabAssSBSw Service Balance Switch of RAB Assignment Procedure
CallHoldSBSw Service Balance Switch of Call holding Procedure
csTrafPrefInd CS Traffic Preferred Indicator
r99PsTrafPrefInd R99 PS Traffic Preferred Indicator
hsTrafPrefInd HS PS Traffic Preferred Indicator
ShareCover Share Cover Indication (utranRelation)
GsmShareCover Share Cover Indication (gsmRelation)
HspaSptMeth(utranCell) HSPA Support Method(utranCell)
HspaSptMeth(externalUt
ranCell) HSPA Support Method(externalUtranCell)
CsBalSwch CS Balance Switch of RAB Assignment Procedure
CsHo4MulRabSwch Switch of CS Handover for CS+PS in Multi-Carrier
Scenario
DcRedirectStaSw Dual Carrier Redirection Strategy Switch
DulCarBalRscpThd Cpich RSCP Threshold for Dual Carrier HSDPA Balance
DulCarBalEcNoThd Cpich EcNo Threshold for Dual Carrier HSDPA Balance
RrcDualCarrSw Dual Carrier Balance Switch of Initial RRC Procedure
HOLDHSPAPLUBALSW HSPA+ Balance Switch of Call Holding Procedure
RABHSPAPLUBALSW HSPA+ Balance Switch of RAB Assignment Procedure
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Abbreviated Name Parameter Name
HSPAPLUSCAPIND HSPA+ Capability Indicator
HSPAPLUBALCAPPRI HSPA+ Balance Priority
RabMeaBalStaSwch Inter-Frequency Balance Switch Based on Measurement
CoverMeaBalSwch Inter-Frequency Balance Switch Based on Measurement
with Overlapping or Covering Relation
SimCompUserNum User Number with Compressed Mode Activation for
Balance Strategy Based On Measurement
MeasBalTimer Timer of Deactivate Compressed Mode for Balance
Strategy Based On Measurement
EcNoQualThrd Cpich Ec/N0 Threshold for Blind Handover
RscpQualThrd Cpich RSCP Threshold for Blind Handover
RrcHsLdBaOnDchSw Switch of HSDPA Load Balance for Signaling on DCH in
RRC Connection Procedure
ldBalHsdCodFacCho Code Factor in HSDPA Throughput Load Balance
ldBalHsdPwrFacCho Power Factor in HSDPA Throughput Load Balance
ldBalHsdBandWidFacC
ho Bandwidth Factor in HSDPA Throughput Load Balance
BalFailOpSwch Switch of Optimization When Load Balance Fail
DREcNoQualThrd Cpich Ec/NO Threshold for Directed Retry Triggered by
Inter-RAT Balancing
DRRscpQualThrd Cpich RSCP Threshold for Directed Retry Triggered by
Inter-RAT Balancing
LdBalHspaStrCho Load Balance Strategy for HSPA Service
LdBalHsuSwch Load Balance Switch for HSUPA Throughput
LdBalHsdNumSwch Load Balance Switch for HSDPA User Number
LdHsdUserNumThd UTRAN Downlink Available Load Balance Threshold
(HSDPA User Number) for HSPA
DeltaHsdUsrNumTd Permitted Payload Difference Downlink Available Load
Threshold in Inter-frequency Cells
U2EBalSwch UTRAN to EUTRAN balance switch
CRESPARA1 Cell Reserved Parameter 1
HoCalRestblLBSwch Load Balance Switch of Handover and Call
Reestablishment Procedure
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Abbreviated Name Parameter Name
HoCalRestblSBSwch Service Balance Switch of Handover and Call
Reestablishment Procedure
HoHspaPlusBalSw HSPA+ Balance Switch of Handover and Call
Reestablishment Procedure
MulRabBlSwch PS+CS balance switch
10.2 Parameter Configurations
10.2.1 Load Balance Switch of Initial RRC Procedure
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information ->Load Balance Switch of Initial RRC Procedure
Parameter configuration
This parameter is a load balancing switch for RRC initial access.
10.2.2 Load Balance Switch of RAB Assignment Procedure
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information ->Load Balance Switch of RAB Assignment Procedure
Parameter configuration
This parameter is a load balance switch which indicates whether the load balance
function is open for RAB assignment procedure.
10.2.3 Load Balance Switch of Call holding Procedure
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
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Information->Load Balance Switch of Call Holding Procedure
Parameter configuration
This parameter is a load balance switch which indicates whether load balance function is
open for call holding procedure. The application scenarios include handover, relocation,
RAB re-establishment and FACH->DCH.
10.2.4 Load balance switch for downlink power
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Load Balance Switch for Downlink Power
Parameter configuration
This parameter is a switch indicating whether load balance based on downlink power is
open or not.
10.2.5 Load Balance Switch for Uplink Interference
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Load Balance Switch for Uplink Interference
Parameter configuration
This parameter is a switch indicating whether load balance based on uplink interference
is open or not.
10.2.6 Load Balance Switch for Code
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Load Balance Switch for Code
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Parameter configuration
This parameter is a switch indicating whether load balance based on code resources is
open or not.
10.2.7 Load Balance Switch for HSDPA Throughput
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information-> Load Balance Switch for HSDPA Throughput
Parameter configuration
This parameter is a switch indicating whether load balance based on HSDPA Throughput
is open or not.
10.2.8 Downlink Power Weight for Load Balance
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Downlink Power Weight for Load Balance (%)
Parameter configuration
This parameter indicates the weight of downlink power resources in several factors of
load balance.
10.2.9 Uplink Interference Weight for Load Balance
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Uplink Interference Weight for Load Balance (%)
Parameter configuration
This parameter indicates the weight of uplink interference in several factors of load
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balance.
10.2.10 Code Weight for Load Balance
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Code Weight for Load Balance (%)
Parameter configuration
This parameter indicates the weight of code resources in several factors of load balance.
10.2.11 HSDPA Throughput Weight for Load Balance
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->HSDPA Throughput Weight for Load Balance (%)
Parameter configuration
This parameter indicates the weight of uplink interference in several factors of load
balance.
10.2.12 UTRAN Downlink Available Load Balance Threshold (Power) for CS
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->UTRAN Downlink Available Load Balance Threshold (Power) for CS (%)
Parameter configuration
This parameter indicates the downlink available Power load threshold of CS service for
load balance between UTRAN cells. If the downlink available Power load of local UTRAN
cell is less than the threshold indicated by this parameter, the downlink load balance
judgment is performed and a UE of the local cell may be balanced to other UTRAN cell.
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10.2.13 Inter-RAT Downlink Available Load Balance Threshold (Power) for
CS
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Inter-RAT Downlink Available Load Balance Threshold (Power) for CS (%)
Parameter configuration
This parameter indicates the downlink power available load threshold of CS service for
load balance between different RAT systems. If the downlink available load of the local
cell is less than the threshold indicated by this parameter, the downlink load balance
judgment is performed and a UE of the local cell may be balanced to other RAT systems.
10.2.14 UTRAN Downlink Available Load Balance Threshold (Power) for R99
PS
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->UTRAN Downlink Available Load Balance Threshold (Power) for R99 PS
(%)
Parameter configuration
This parameter indicates the downlink power available load threshold of R99 PS service
for load balance between UTRAN cells. If the downlink available load of local UTRAN
cell is less than the threshold indicated by this parameter, the downlink load balance
judgment is performed and a UE of the local cell may be balanced to other UTRAN cell.
10.2.15 Permitted Payload Difference Downlink Available Load Threshold in
Inter-frequency Cells (Power)
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Permitted Payload Difference Downlink Available Load Threshold in
Inter-frequency Cells (Code) (%)
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Parameter configuration
This parameter indicates the permitted downlink available TCP load difference threshold
between inter-frequency cells. It is used to evaluate the load of a cell.
10.2.16 UTRAN Uplink Available Load Balance Threshold (Interference ) for
CS
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->UTRAN Uplink Available Load Balance Threshold (Interference) for CS(%)
Parameter configuration
This parameter indicates the uplink available load threshold of CS service for load
balance between UTRAN cells. If the uplink available load of local UTRAN cell is less
than the threshold indicated by this parameter, the uplink load balance judgment is
performed and a UE of the local cell may be balanced to other UTRAN cell.
10.2.17 Inter-system Uplink Available Load Balance Threshold (Interference)
for CS
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Inter-System Uplink Available Load Balance Threshold (Interference) for
CS (%)
Parameter configuration
This parameter indicates the uplink available load threshold of CS service for load
balance between different RAT systems. If the uplink available load local cell is less than
the threshold indicated by this parameter, performs the uplink load balance judgment and
a UE of the local cell may be balanced to other RAT systems.
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10.2.18 UTRAN Uplink Available Load Balance Threshold (Interference) for
R99 PS
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->UTRAN Uplink Available Load Balance Threshold (Interference) for R99 PS
(%)
Parameter configuration
This parameter indicates the uplink available load threshold of R99 PS service for load
balance between UTRAN cells. If the uplink available load of local UTRAN cell is less
than the threshold indicated by this parameter, the uplink load balance judgment is
performed and a UE of the local cell may be balanced to other UTRAN cell.
10.2.19 Permitted Payload Difference Uplink Available Load Threshold in
Inter-frequency Cells (Interference)
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Permitted Payload Difference Uplink Available Load Threshold in
Inter-frequency Cells (Interference) (%)
Parameter configuration
This parameter indicates the permitted uplink available RTWP load difference threshold
between inter-frequency cells. It is used to evaluate the load (Weight) of a cell.
10.2.20 UTRAN Downlink Available Load Balance Threshold (Code) for CS
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->UTRAN Downlink Available Load Balance Threshold (Code) for CS (%)
Parameter configuration
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This parameter indicates the available channelization code load balance threshold of CS
service. If the downlink available channelization code usage ratio is less than the
threshold indicated by this parameter, the downlink load balance judgment is performed
and some UEs may be balanced to other UTRAN cell.
10.2.21 UTRAN Downlink Available Load Balance Threshold (Code) for R99
PS
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->UTRAN Downlink Available Load Balance Threshold (Code) for R99 PS
(%)
Parameter configuration
This parameter indicates the downlink available channelization code load balance
threshold of R99 PS service. If the local UTRAN cell‟s downlink available channelization
code usage ratio is less than the threshold indicated by this parameter, the downlink load
balance judgment is performed and some UEs may be balanced to other UTRAN cell.
10.2.22 Permitted Payload Difference Downlink Available Load Threshold in
Inter-frequency Cells (Code)
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Permitted Payload Difference Downlink Available Load Threshold in
Inter-frequency Cells (Code) (%)
Parameter configuration
This parameter indicates the code resource available load difference threshold between
inter-frequency cells. It is used to evaluate the load (Weight) of a cell.
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10.2.23 UTRAN Downlink Available Load Balance Threshold (HSDPA
Throughput) for HSDPA
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->UTRAN Downlink Available Load Balance Threshold (HSDPA Throughput)
for HSDPA (%)
Parameter configuration
This parameter indicates the downlink available HSDPA throughput threshold for load
balance between UTRAN cells. If the downlink available HSDPA throughput of local
UTRAN cell is less than the threshold indicated by this parameter, the downlink load
balance judgment is performed and a UE of the local cell may be balanced to other
UTRAN cell.
10.2.24 Permitted Payload Difference Downlink Available Load Threshold in
Inter-frequency Cells (HSDPA Throughout)
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information -> Permitted Payload Difference Downlink Available Load Threshold in
Inter-frequency Cells (HSDPA Throughout) (%)
Parameter configuration
This parameter indicates the HSDPA throughput available load difference threshold
between inter-frequency cells. It is used to evaluate the load (Weight) of a cell.
10.2.25 Service Balance Switch of Initial RRC Procedure
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Service Balance Switch of Initial RRC Procedure
Parameter configuration
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This parameter is a service balance switch which indicates whether the RRC service
balance function is open for initial RRC procedure used for accessing.
10.2.26 Service Balance Switch of RAB Assignment Procedure
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Service Balance Switch of RAB Assignment Procedure
Parameter configuration
This parameter is a load balance switch which indicates whether the load service
function is open for RAB assignment procedure.
10.2.27 Service Balance Switch of Call holding Procedure
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Service Balance Switch of Call Holding Procedure
Parameter configuration
This parameter is a load balance switch which indicates whether load balance function is
open for call holding procedure. The application scenarios include handover, relocation,
RAB re-establishment and FACH->DCH.
10.2.28 CS Traffic Preferred Indicator
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->UTRAN Cell ->
Preferred Traffic Type
Parameter configuration
This parameter indicates whether the cell prefers CS service. Each cell can be set to
voice service preferred, data service preferred or no preferred
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(CsTrafPrefInd/r99PsTrafPrefInd/hsTrafPrefInd).
10.2.29 R99 PS Traffic Preferred Indicator
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->UTRAN Cell ->
Preferred Traffic Type
Parameter configuration
This parameter indicates whether the cell prefers R99 PS service. Each cell can be set to
voice service preferred, data service preferred or no preferred
(CsTrafPrefInd/r99PsTrafPrefInd/hsTrafPrefInd).
10.2.30 HS PS Traffic Preferred Indicator
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->UTRAN Cell ->
Preferred Traffic Type
Parameter configuration
This parameter indicates whether the cell prefers HS PS service. Each cell can be set to
voice service preferred, data service preferred or no preferred
(CsTrafPrefInd/r99PsTrafPrefInd/hsTrafPrefInd).
10.2.31 Share Cover Indication (utranRelation)
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Neighbouring
Cell->Neighbouring Cell ->Share Cover Indication
Parameter configuration
This parameter describes the location of the serving cell and neighboring cell.
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10.2.32 Share Cover Indication (gsmRelation)
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->GSM Neighbouring
Cell->GSM Neighbouring Cell ->Share Cover Indication
Parameter configuration
This parameter describes the location of the serving cell and GSM neighboring cell.
10.2.33 HSPA Support Method(utranCell)
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->UTRAN Cell ->HSPA
Support Method
Parameter configuration
This parameter indicates the support of HSPA in the cell.
10.2.34 HSPA Support Method(externalUtranCell)
OMC path
GUI: View-> UMTS Logical Function Configuration->External RNC Function ->External
UTRAN Cell->External UTRAN Cell ->HSPA Support Method
Parameter configuration
This parameter indicates the support of HSPA in the cell.
10.2.35 CS Balance Switch of RAB Assignment Procedure
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->CS Balance Switch of RAB Assignment Procedure
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Parameter configuration
This parameter is a CS balance switch which indicates whether the balance function is
open for CS service during RAB assignment procedure.
10.2.36 Switch of CS Handover for CS+PS in Multi-Carrier Scenario
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Service of CS Handover for CS+PS in Multi-Carrier Scenario
Parameter configuration
This parameter is used in the following scenario: For multi-RAB service, PS service is
released and only R99 CS service remains, if the cell is R5+R6+R99 or R5+R99 and
only HS PS is preferred traffic, UE will be balanced to a cell with shared coverage
relation, R99 service available and not only HS PS preferred when the parameter value
is “open”.
10.2.37 Dual Carrier Redirection Strategy Switch
OMC path
GUI: View->UMTS Logical Function Configuration->UMTS Logical Function
Configuration ->Dual Carrier Redirection Strategy Switch
Parameter configuration
If this parameter value is “1:On”, PS Service is requested by UE with DC capability from
non-DC cell can be redirected to its available DC capability inter-frequency neighbor cell
with “3:Contained in” relationship.
10.2.38 Cpich RSCP Threshold for Dual Carrier HSDPA Balance
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Cpich RSCP Threshold for Dual Carrier HSDPA Balance
Parameter configuration
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When measurement quality is “RSCP”, the target redirection cell‟s quality must be better
than this threshold.
10.2.39 Cpich EcNo Threshold for Dual Carrier HSDPA Balance
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Cpich EcNo Threshold for Dual Carrier HSDPA Balance
Parameter configuration
When measurement quality is “EcNo”, the target redirection cell‟s quality must be better
than this threshold.
10.2.40 Dual Carrier Balance Switch of Initial RRC Procedure
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Dual Carrier Balance Switch of Initial RRC Procedure
Parameter configuration
This parameter is a load balancing switch for DC service when RRC initial access.
10.2.41 HSPA+ Balance Switch of Call Holding Procedure
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->HSPA+ Balance Switch of Call Holding Procedure
Parameter configuration
This parameter can be used to control whether a certain HSPA+ feature is taken into
account during Call keeping stage.
10.2.42 HSPA+ Balance Switch of RAB Assignment Procedure
OMC path
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GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->HSPA+ Balance Switch of RAB Assignment Procedure
Parameter configuration
This parameter can be used to control whether a certain HSPA+ feature is taken into
account during RAB Assignment stage.
10.2.43 HSPA+ Capability Indicator
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->HSPA+ Capability Indicator
Parameter configuration
This parameter will be used for determining which HSPA+ feature will be used during
load balancing when many HSPA+ features are supported by the cell and UE.
10.2.44 HSPA+ Balance Priority
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->HSPA+ Balance Priority
Parameter configuration
This parameter will be used for determining the HSPA+ features‟ absolute priorities,
which will be used during load balancing when many HSPA+ features are supported by
the cell and UE.
10.2.45 Inter-Frequency Balance Switch Based on Measurement
OMC path
GUI: View-> UMTS Logical Function Configuration->UMTS Logical Function
Configuration ->Inter-Frequency Balance Switch Based on Measurement with
Overlapping or Covering Relation
Parameter configuration
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This parameter will be used for determining whether to perform Measurement-based
Multi-carrier Interoperation.
When the switch is closed, Measurement -based Multi-carrier Interoperation is not
performed.
When the switch is open, Measurement -based Multi-carrier Interoperation is performed.
10.2.46 Inter-Frequency Balance Switch Based on Measurement with
Overlapping or Covering Relation
OMC path
GUI: View-> UMTS Logical Function Configuration->UMTS Logical Function
Configuration >Inter-Frequency Balance Switch Based on Measurement with
Overlapping or Covering Relation
Parameter configuration
This parameter will be used for determining whether to perform Measurement-based
Multi-carrier Interoperation for overlap/cover neighbor cells.
When the switch is closed, Measurement -based Multi-carrier Interoperation for
overlap/cover neighbor cells is not performed.
When the switch is open, Measurement -based Multi-carrier Interoperation for
overlap/cover neighbor cells is performed.
10.2.47 User Number with Compressed Mode Activation for Balance
Strategy Based On Measurement
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Extended Info of
UTRAN Cell ->User Number with Compressed Mode Activation for Balance Strategy
Based On Measurement
Parameter configuration
This parameter will be used for determining how many users are allowed to activate the
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compressed mode for Balance Strategy Based On Measurement simultaneously.
10.2.48 Timer of Deactivate Compressed Mode for Balance Strategy Based
On Measurement
OMC path
GUI: View-> UMTS Logical Function Configuration->UMTS Logical Function
Configuration ->Timer of Deactivate Compressed Mode for Balance Strategy Based On
Measurement
Parameter configuration
This parameter will be used for determining the length of the timer for users to activate
the compressed mode for Balance Strategy Based On Measurement.
10.2.49 Cpich Ec/N0 Threshold for Blind Handover
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->UTRAN Cell ->Cpich
Ec/N0 Threshold for Blind Handover
Parameter configuration
This parameter will be used for determining whether to perform blind handover based on
the Ec/N0 level.
10.2.50 Cpich RSCP Threshold for Blind Handover
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->UTRAN Cell ->Cpich
RSCP Threshold for Blind Handover
Parameter configuration
This parameter will be used for determining whether to perform blind handover based on
the RSCP level.
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10.2.51 Load Balance Switch for Bandwidth
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Load Balance Switch for Bandwidth
Parameter configuration
This parameter is a switch indicating whether load balance based on bandwidth is open
or not. If the parameter value is "open", RNC perform load balance based on bandwidth
among different carriers and balance users to low load carrier to offer better service. If
the parameter value is "closed", it does not need to consider load balance based on
bandwidth.
10.2.52 HSUPA Throughput Weight for Load Balance
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->HSUPA Throughput Weight for Load Balance
Parameter configuration
This parameter indicates the weight of HSDPA throughput. When "LdBalHsSwch" is
opened, the parameter value is bigger, HSUPA throughput is the key factor in load
evaluation and load balance based on HSUPA throughput is triggered easier. Otherwise,
if the value is smaller, it is not easy to trigger load balancing based on HSUPA
throughput.
10.2.53 UTRAN Uplink Available Load Balance Threshold (HSUPA
Throughput) for HSUPA
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->UTRAN Uplink Available Load Balance Threshold (HSUPA Throughput) for
HSUPA
Parameter configuration
This parameter indicates the uplink available HSUPA throughput threshold for load
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balance between UTRAN cells. If the available HSUPA throughput of local UTRAN cell is
less than the threshold indicated by this parameter, the load balance judgment is
performed and a UE of the local cell may be balanced to other UTRAN cell.
10.2.54 Permitted Payload Difference Available Load Threshold in
Inter-frequency Cells (HSUPA Throughput)
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->Permitted Payload Difference Downlink Available Load Threshold in
Inter-frequency Cells (HSUPA Throughput)
Parameter configuration
This parameter indicates the uplink available HSUPA throughput threshold for load
balance between inter-frequency cells used to calculate load of source cell. The bigger
the value is, the harder it is for load balancing to be triggered.
10.2.55 Equivalent HSPA Users
OMC path
GUI: View-> UMTS Logical Function Configuration->QOS Function->Qos Basic
Configuration ->Equivalent HSPA Users
Parameter configuration
This parameter indicates the equivalent HSPA users.
10.2.56 GSM Cell’s Carrier Number
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->GSM Cell‟s Carrier Number
Parameter configuration
This parameter indicates GSM Cell‟s Carrier Number.
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10.2.57 User Number Offset of UTRAN for Balance
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->User Number Offset of UTRAN for Balance
Parameter configuration
This parameter indicates the balance tendency when UTRNA neighboring cell, GSM
neighboring cells in Multi-Mode system and common GSM neighboring cells exist
simultaneously. The larger the value is, the easier neighboring cell of UTRAN will be
balanced.
10.2.58 User Number Offset of GSM in Multi-Mode System for Balance
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->User Number Offset of GSM in Multi-Mode System for Balance
Parameter configuration
This parameter indicates the balance tendency when UTRNA neighboring cell, GSM
neighboring cells in multi-mode system and common GSM neighboring cells exist
simultaneously. The larger the value is, the easier neighboring cell of GSM in multi-mode
system will be balanced.
10.2.59 User Number Offset of GSM for Balance
OMC path
GUI: View->UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information->User Number Offset of GSM for Balance
Parameter configuration
This parameter indicates the balance tendency when UTRNA neighboring cell, GSM
neighboring cells in multi-mode system and common GSM neighboring cells exist
simultaneously. The larger the value is, the easier neighboring cell of common GSM
system will be balanced.
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10.2.60 TCP Load Low Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->TCP Load Low Threshold
Parameter configuration
The parameter indicates the lower TCP load threshold. When the TCP payload of a cell
is lower than the value indicated by the parameter, it means the TCP load state of the cell
is low.
10.2.61 TCP Load Middle Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->TCP Load Middle Threshold
Parameter configuration
The parameter indicates the middle TCP load threshold. When the TCP payload of a cell
is bigger than TCPLoadLowThd and lower than the value indicated by the parameter, it
means the TCP load state of the cell is moderate.
10.2.62 TCP Load High Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->TCP Load High Threshold
Parameter configuration
The parameter indicates the upper TCP load threshold. If the TCP payload of a cell is
bigger than TCPLoadMidThd and lower than the value indicated by the parameter, it
means the TCP load state of the cell is high. If the payload of a cell is bigger than the
value indicated by the parameter, the TCP load state of the cell is overload.
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10.2.63 RTWP Load Low Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->RTWP Load Low Threshold
Parameter configuration
The parameter indicates the lower RTWP load threshold. When the RTWP payload of a
cell is lower than the value indicated by the parameter, it means the RTWP load state of
the cell is low.
10.2.64 RTWP Load Middle Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->RTWP Load Middle Threshold
Parameter configuration
The parameter indicates middle RTWP load threshold. When the RTWP payload of a cell
is bigger than RtwpLoadLowThd and lower than the value indicated by the parameter, it
means the RTWP load state of the cell is moderate.
10.2.65 RTWP Load High Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->RTWP Load High Threshold
Parameter configuration
The parameter indicates upper RTWP load threshold. If the RTWP payload of a cell is
bigger than RtwpLoadMidThd and lower than the value indicated by the parameter, it
means the RTWP load state of the cell is high. If the payload of a cell is greater than the
value indicated by the parameter, the RTWP load state of the cell is overload.
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10.2.66 HSDPA User Number Low Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->HSDPA User Number Low Threshold
Parameter configuration
The parameter indicates the lower threshold of the number of HSDPA users. If the
number of HSDPA users is lower than the value indicated by this parameter, the HSDPA
user load state of the cell is low.
10.2.67 HSDPA User Number Middle Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->HSDPA User Number Middle Threshold
Parameter configuration
The parameter indicates the middle threshold of the number of HSDPA users. If the
number of HSDPA users of a cell is greater than DPAUNumLowThd and lower than the
value indicated by this parameter, it means the HSDPA user load state is moderate; if the
number of HSDPA users is greater than the value indicated by this parameter, it means
that the HSDPA user load state is high.
10.2.68 HSUPA User Number Low Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->HSUPA User Number Low Threshold
Parameter configuration
The parameter indicates the lower threshold of the number of HSUPA users. If the
number of HSUPA users is lower than the value indicated by this parameter, the HSUPA
user load state of the cell is low.
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10.2.69 HSUPA User Number Middle Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->HSUPA User Number Middle Threshold
Parameter configuration
The parameter indicates the middle threshold of the number of HSUPA users. If the
number of HSUPA users of a cell is greater than UPAUNumLowThd and lower than the
value indicated by this parameter, it means the HSUPA user load state is moderate; if the
number of HSUPA users is greater than the value indicated by this parameter, it means
that the HSUPA user load state is high.
10.2.70 MBMS User Number Low Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->MBMS User Number Low Threshold
Parameter configuration
The parameter indicates the lower threshold of the number of MBMS users. If the
number of MBMS users is lower than the value indicated by this parameter, the MBMS
user load state of the cell is low.
10.2.71 MBMS User Number Middle Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->MBMS User Number Middle Threshold
Parameter configuration
The parameter indicates the middle threshold of the number of MBMS users. If the
number of MBMS users of a cell is greater than MbmsUNumLowThd and lower than the
value indicated by this parameter, it means the MBMS user load state is moderate; if the
number of MBMS users is greater than the value indicated by this parameter, it means
that the MBMS user load state is high.
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10.2.72 Signal User Number Low Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->Signal User Number Low Threshold
Parameter configuration
The parameter indicates the lower threshold of the number of signal users. If the number
of signal users is lower than the value indicated by this parameter, the signal user load
state of the cell is low.
10.2.73 Signal User Number Middle Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->Signal User Number Middle Threshold
Parameter configuration
The parameter indicates the middle threshold of the number of signal users. If the
number of signal users of a cell is greater than SigUNumLowThd and lower than the
value indicated by this parameter, it means the signal user load state is moderate; if the
number of signal users is greater than the value indicated by this parameter, it means
that the signal user load state is high.
10.2.74 Code Load Low Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->Code Load Low Threshold
Parameter configuration
The parameter indicates the lower code load threshold. When the code payload of a cell
is lower than the value indicated by the parameter, it means the code load state of the
cell is low.
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10.2.75 Code Load Middle Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->Code Load Middle Threshold
Parameter configuration
The parameter indicates the middle Code load threshold. If the Code payload of a cell is
lower than the value indicated by the parameter, it means the Code load state of the cell
is moderate. If the occupied code resource is greater than the value indicated by this
parameter, it means that the code resource load state is high.
10.2.76 CE Load Low Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->CE Load Low Threshold
Parameter configuration
The parameter indicates the lower CE load threshold. When the CE payload of a cell is
lower than the value indicated by the parameter, it means the CE load state of the cell is
low.
10.2.77 CE Load Middle Threshold
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Load Control
Information ->CE Load Middle Threshold
Parameter configuration
The parameter indicates the middle CE load threshold. If the CE payload of a cell is
lower than the value indicated by the parameter, it means the CE load state of the cell is
moderate. If the occupied code resource is greater than the value indicated by this
parameter, it means that the code resource load state is high.
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10.2.78 Load Balance Scene
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->UTRAN Cell ->Load
Balance Scene
Parameter configuration
The parameter indicates typical load balance scenarios. For each scenario, the
corresponding load balance parameters can be set as different values.
10.2.79 Switch of HSDPA Load Balance for Signaling on DCH in RRC
Connection Procedure
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information-> Switch of HSDPA Load Balance for Signaling on DCH in RRC Connection
Procedure
Parameter configuration
During initial RRC procedure, when signaling sets up on DCH and it is PS service (refer
to chapter 4.1) and UE‟s version is R5 or later, if RrcHsLdBaOnDchSw is “on”, strategy of
HSDPA load balance is used; otherwise, R99‟s is used.
10.2.80 Code Factor in HSDPA Throughput Load Balance
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information-> Code Factor in HSDPA Throughput Load Balance
Parameter configuration
HSDPA maximum throughput of the cell = min(HSDPA maximum throughput which is
provided by HSDPA available code in the cell, HSDPA maximum throughput which is
provided by HSDPA available power in the cell, HSDPA maximum throughput which is
provided by available transmission band in the cell)
Where, the three factors are controlled by ldBalHsdCodFacCho,
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ldBalHsdPwrFacCho, and ldBalHsdBandWidFacCho.
10.2.81 Power Factor in HSDPA Throughput Load Balance
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information-> Power Factor in HSDPA Throughput Load Balance
Parameter configuration
HSDPA maximum throughput of the cell = min(HSDPA maximum throughput which is
provided by HSDPA available code in the cell, HSDPA maximum throughput which is
provided by HSDPA available power in the cell, HSDPA maximum throughput which is
provided by available transmission band in the cell)
Where, the three factors are controlled by ldBalHsdCodFacCho,
ldBalHsdPwrFacCho, and ldBalHsdBandWidFacCho.
10.2.82 Bandwidth Factor in HSDPA Throughput Load Balance
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information-> Bandwidth Factor in HSDPA Throughput Load Balance
Parameter configuration
HSDPA maximum throughput of the cell = min(HSDPA maximum throughput which is
provided by HSDPA available code in the cell, HSDPA maximum throughput which is
provided by HSDPA available power in the cell, HSDPA maximum throughput which is
provided by available transmission band in the cell)
Where, the three factors are controlled by ldBalHsdCodFacCho, ldBalHsdPwrFacCho,
and ldBalHsdBandWidFacCho.
10.2.83 Switch of Optimization When Load Balance Fail
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
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Information-> Switch of Optimization When Load Balance Fail
Parameter configuration
Parameter BalFailOpSwch controls the function that enables RB to be set up on the
source cell if load balancing failed. When this parameter is “on”, if the UE sends a Uu
Failure response during any balance procedure except initial RRC procedure and
relocation, the RNC tries to set up RB on source cell.
10.2.84 Cpich Ec/NO Threshold for Directed Retry Triggered by Inter-RAT
Balancing
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load
Balance Information-> Cpich Ec/NO Threshold for Directed Retry Triggered by
Inter-RAT Balancing
Parameter configuration
The 3G cell‟s quality must be evaluated before directed retry. If CpichEcNo of the cell is
bigger than DREcNoQualThrd or CpichRSCP of the cell is bigger than DRRscpQualThrd
(if both CpichEcNo and CpichRSCP are used, the two criteria must be satisfied together),
directed retry will be implemented; otherwise, directed retry will not be used.
10.2.85 Cpich RSCP Threshold for Directed Retry Triggered by Inter-RAT
Balancing
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information-> Cpich Ec/NO Threshold for Directed Retry Triggered by Inter-RAT
Balancing
Parameter configuration
The 3G cell‟s quality must be evaluated before directed retry. If CpichEcNo of the cell is
bigger than DREcNoQualThrd or CpichRSCP of the cell is bigger than DRRscpQualThrd
(if both CpichEcNo and CpichRSCP are used, the two criteria must be satisfied together),
directed retry will be implemented; otherwise, directed retry will not be used.
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10.2.86 Load Balance Strategy for HSPA Service
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information-> Load Balance Strategy for HSPA Service
Parameter configuration
The load of HSPA is evaluated by HSPA throughput or HSPA user number, and
controlled by LdBalHspaStrCho.
10.2.87 Load Balance Switch for HSUPA Throughput
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information-> Load Balance Switch for HSUPA Throughput
Parameter configuration
This parameter is a switch indicating whether load balance based on HSUPA Throughput
is open or not.
10.2.88 Load Balance Switch for HSDPA User Number
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information-> Load Balance Switch for HSDPA User Number
Parameter configuration
This parameter is a switch indicating whether load balance based on HSDPA User
Number is open or not
10.2.89 UTRAN Downlink Available Load Balance Threshold (HSDPA User
Number) for HSPA
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information-> UTRAN Downlink Available Load Balance Threshold (HSDPA User
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Number) for HSPA
Parameter configuration
All the cells are separately ranked in descending order according to (LdHsdUserNumThd
–HSDPA user number).
10.2.90 Permitted Payload Difference Downlink Available Load Threshold in
Inter-frequency Cells
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information-> Permitted Payload Difference Downlink Available Load Threshold in
Inter-frequency Cells
Parameter configuration
For a source cell, HSDPA user number = HSDPA user number-DeltaHsdUsrNumTd
10.2.91 UTRAN to EUTRAN balance switch
OMC path
GUI: View-> UMTS Logical Function Configuration->UTRAN Cell->Power Load Balance
Information-> UTRAN to EUTRAN balance switch
Parameter configuration
This parameter controls the function of UTRAN -> EUTRAN Service Balance.
10.2.92 Cell Reserved Parameter 1
OMC path
GUI: Managed Element ->UMTS Logical Function Configuration->UTRAN
Cell->Extended Info of UTRAN Cell->Cell Reserved Parameter 1
Parameter configuration
The parameter indicates the service type category of "originalLowPrioritySignalling" and
"terminatingLowPrioritySignalling" in RRC Connection Request.
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10.2.93 Load Balance Switch of Handover and Call Reestablishment Procedure
OMC path
GUI: Managed Element ->UMTS Logical Function Configuration->UTRAN Cell->Load
Balance Information->Load Balance Switch of Handover and Call Reestablishment
Procedure
Parameter configuration
This parameter is a load balance switch which indicates whether load balance function is
supported for call holding procedure.
10.2.94 Service Balance Switch of Handover and Call Reestablishment Procedure
OMC path
GUI: Managed Element ->UMTS Logical Function Configuration->UTRAN Cell->Load
Balance Information->Service Balance Switch of Handover and Call Reestablishment
Procedure
Parameter configuration
This parameter is a service balance switch which indicates whether load balance
function is supported for call holding procedure.
10.2.95 HSPA+ Balance Switch of Handover and Call Reestablishment Procedure
OMC pathpath
GUI: Managed Element ->UMTS Logical Function Configuration->UTRAN Cell->Load
Balance Information->HSPA+ Balance Switch of Handover and Call Reestablishment
Procedure
Parameter configuration
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This parameter is an HSPA+ balance switch which indicates whether load balance
function is supported for call holding procedure.
10.2.96 PS+CS balance switch
OMC path
GUI: Managed Element ->UMTS Logical Function Configuration->UTRAN Cell->Load
Balance Information-> PS+CS balance switch
Parameter configuration
This parameter is used in the following scenario: the UE has PS and initial CS as the
second RAB on a cell without CS preferred. If the current cell has overlap/covers
neighboring cell with CS preferred and this switch is "on", the multi-RAB is balanced to
the neighboring cell.
11 Counters and Alarms
11.1 Counter List
Counter No. Description
C310514818 Number of DCH to HSDPA direct attempt, R99 cell to HSDPA cell
C310514819 Number of DCH to HSDPA failure, Configuration unsupport
C310514820 Number of DCH to HSDPA failure, Configuration invalid
C310514821 Number of DCH to HSDPA failure, Configuration Incomplete
C310514822 Number of DCH to HSDPA failure, Physical Channel Failure
C310514823 Number of DCH to HSDPA failure, Incompatible Simultaneous
Reconfiguration
C310514824 Number of DCH to HSDPA failure, Compress Mode Error
C310514825 Number of DCH to HSDPA failure, Protocol Error
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C310514826 Number of DCH to HSDPA failure, Cell Update Occurred
C310514827 Number of DCH to HSDPA failure, No Reply
C310514828 Number of DCH to HSDPA failure, Other Causes
C311765664 Number of load balance attempt:RRC start access
C311765665 Number of load balance attempt:DRBC and channel changing
C311765666 Number of load balance attempt:call reestablish
C311765667 Number of load balance attempt:new service setup in phase of RAB
C311765668 Number of load balance attempt:handover
C311765670 Number of load balance attempt:incoming relocation balance
C311765671 Number of load balance success:RRC start access
C311765672 Number of load balance success:DRBC and channel changing
C311765673 Number of load balance success:call reestablish
C311765674 Number of load balance success:new service setup in phase of RAB
C311765675 Number of load balance success:handover
C311765677 Number of load balance success:incoming relocation balance
C311765678 Number of load balance attempt:DL power
C311765679 Number of load balance attempt:code resource
C311765680 Number of load balance attempt:UL RSEPS
C311765681 Number of load balance attempt:HSDPA capability
C311763547 Number of load balance attempt:HSPA user
C311763548 Number of load balance attempt:E-DCH capability
C311765682 Number of load balance success:DL power
C311765683 Number of load balance success:code resource
C311765684 Number of load balance success:UL RSEPS
C311765685 Number of load balance success:HSDPA user capability
C311763549 Number of load balance success:HSPA user
C311763550 Number of load balance success:E-DCH capability
C313353543 Number of outgoing hard handover attempt,HSPA+ capability
required
C313353544 Number of outgoing hard handover attempt,service prfer required
C313353545 Number of outgoing hard handover failed,HSPA+ capability required
C313353546 Number of outgoing hard handover failed,service prfer required
C310030714 Max Number of including HSDPA user in the best cell
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C310030462 Average Number of including only HSDPA + HSUPA users in the
best cell
11.2 Alarm List
This feature has no relative alarm.
12 Glossary
CS Circuit switched
HCS Hierarchical Cell Structure
HSDPA High speed downlink packet access
HSUPA High speed uplink packet access
PS Packet switched
RAB Radio access bearer
RNC Radio network controller
RRC Radio resource control
RSCP Received Signal Code Power
RTWP Received total wide band power
SF Spreading Factor
UE User equipment
UMTS Universal mobile telecommunication system