eRAN
eRAN
DL CoMP Feature Parameter
DL CoMP Feature Parameter
Description
Description
IIssssuuee 0022D
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Huawei Technologies Co., Ltd.
Huawei Technologies Co., Ltd.
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Contents
Contents
1 About T
1 About T
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1.1 Scope...
1.1 Scope...11
1.2 Disclaime
1.2 Disclaimer for Trial Features...1r for Trial Features...1
1.3 Intended
1.3 IntendedAudience...2Audience...2
1.4 Change H
1.4 Change History...istory...22
1.5 Difference
1.5 Differences Between eNodeB Types...s Between eNodeB Types...33
2 Overvie
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2.1 Introducti
2.1 Introduction...on...44
2.2 Benefits...
2.2 Benefits...6...6
2.3 Related Concepts...
2.3 Related Concepts...66
2.4 Architectu
2.4 Architecture...re...66
3 Technica
3 Technica
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Description...
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3.1 Selection
3.1 Selection of a Coordinating Ceof a Coordinating Cell Set...ll Set...99
3.2 Selection
3.2 Selection of CoMP UEs of CoMP UEs and Coordinating Cells...9and Coordinating Cells...9
3.2.1 Entering
3.2.1 Entering the DPS Mode...9 the DPS Mode...9
3.2.2 Entering
3.2.2 Entering the JT Mode the JT Mode...1111
3.2.3 Exiting the DPS
3.2.3 Exiting the DPS or JT Mode...11or JT Mode...11
3.3 Multi-Cell
3.3 Multi-Cell Coordinated T Coordinated Transmission...ransmission...1212
4 Related
4 Related
Features...
Features...
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Impact...
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6 Enginee
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6.1 When to U
6.1 When to Use...se...1717
6.2 Required I
6.2 Required Information...nformation...1717
6.3 Planning..
6.3 Planning...2121
6.3.1 RF Plan
6.3.1 RF Planning...ning...2121
6.3.2 Network
6.3.2 Network Planning... Planning...2121
6.3.3 Hardwar
6.3.3 Hardwar e Planninge Planning...2121
6.4
6.4 Deployment...Deployment...2121
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6.4.4 Hardware Adjustment...22
6.4.4 Hardware Adjustment...22
6.4.5 Data Preparation and Feature
6.4.5 Data Preparation and Feature Activation...Activation...22...22
6.4.5.1 Data Preparation...
6.4.5.1 Data Preparation...2222
6.4.5.2 Using the CME...
6.4.5.2 Using the CME...2626
6.4.5.3 Using MML Commands...26 6.4.5.3 Using MML Commands...26 6.4.5.4 MML Command Examples... 6.4.5.4 MML Command Examples...2727 6.4.6 Activation Observation...27 6.4.6 Activation Observation...27 6.4.7 Deactivation... 6.4.7 Deactivation...2727
6.4.7.1 Using the CME...
6.4.7.1 Using the CME...2828
6.4.7.2 Using MML Commands...28 6.4.7.2 Using MML Commands...28 6.4.7.3 MML Command Examples... 6.4.7.3 MML Command Examples...2828 6.4.8 Reconfiguration... 6.4.8 Reconfiguration...2828 6.5 Performance
6.5 Performance Monitoring...Monitoring...28...28
6.6 Parameter Optimization... 6.6 Parameter Optimization...3030 6.7 Possible Issues... 6.7 Possible Issues...3030
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About This Document
About This Document
1.1 Scope
1.1 Scope
This document describes LAOFD-120201 DL CoMP (Trial), including its
This document describes LAOFD-120201 DL CoMP (Trial), including its technicaltechnical principles, related fe
principles, related features, network impaatures, network impact, and engineering guct, and engineering guidelines.idelines. Any parameters, alarms, counters, or managed objects
Any parameters, alarms, counters, or managed objects (MOs) described herein apply only to(MOs) described herein apply only to the corresponding software release. For future software releases, refer to the
the corresponding software release. For future software releases, refer to the correspondingcorresponding updated product documentation.
updated product documentation.
This document applies only to LTE FDD. Any "LTE" in this document refers to LTE FDD, This document applies only to LTE FDD. Any "LTE" in this document refers to LTE FDD, and "eNodeB" refers to LTE FDD eNodeB.
and "eNodeB" refers to LTE FDD eNodeB.
1.2 Disclaimer for Trial Features
1.2 Disclaimer for Trial Features
Trial features are features that are not yet
Trial features are features that are not yet ready for full commercial release for ready for full commercial release for certaincertain reasons. For example, the industry
reasons. For example, the industry chain (terminals/CN) may not be chain (terminals/CN) may not be sufficiently compatible.sufficiently compatible. However
However, these features can still , these features can still be used for tbe used for testing purposes or commercial network trials.esting purposes or commercial network trials. Anyone who desires to use the trial
Anyone who desires to use the trial features shall contact Huawei and enter into afeatures shall contact Huawei and enter into a
memorandum of understanding (MoU) with Huawei prior to an official application of such memorandum of understanding (MoU) with Huawei prior to an official application of such trial features. Trial features are not for sale in the current version but customers may try them trial features. Trial features are not for sale in the current version but customers may try them for free.
for free.
Customers acknowledge and undertake that trial features may have a certain degree of risk Customers acknowledge and undertake that trial features may have a certain degree of risk due to absence of commercial testing. Before using them, customers shall fully understand not due to absence of commercial testing. Before using them, customers shall fully understand not only the expected benefits of such trial features but also the
only the expected benefits of such trial features but also the possible impact they may exert onpossible impact they may exert on the network. In addition,
the network. In addition, customers acknowledge and undertake that since trial customers acknowledge and undertake that since trial features arefeatures are free, Huawei is not liable for any trial
free, Huawei is not liable for any trial feature malfunctions or any losses incurred by using thefeature malfunctions or any losses incurred by using the trial features. Huawei does not promise that problems with trial features will
trial features. Huawei does not promise that problems with trial features will be resolved inbe resolved in the current version. Huawei reserves the rights to convert trial features into commercial the current version. Huawei reserves the rights to convert trial features into commercial
features in later R/C versions. If trial features are converted into commercial features in a later features in later R/C versions. If trial features are converted into commercial features in a later version, customers shall pay a licensing fee to obtain
version, customers shall pay a licensing fee to obtain the relevant licenses prior to using thethe relevant licenses prior to using the said commercial features. If a customer fails to purchase such a license, the trial feature(s) said commercial features. If a customer fails to purchase such a license, the trial feature(s) will be invalidated automatically when the product is upgraded.
will be invalidated automatically when the product is upgraded. DL CoMP Feature Parameter Description
1.3 Intended Audience
1.3 Intended Audience
This document is intended for personnel who: This document is intended for personnel who:
l
l Need to understand the Need to understand the features describfeatures described hereined herein
l
l Work with Huawei productsWork with Huawei products
1.4 Change History
1.4 Change History
This section provides information about
This section provides information about the changes in different document versions. There arethe changes in different document versions. There are two types of changes:
two types of changes:
l
l Feature changeFeature change
Changes in features and parameters of a specified version as well as the affected entities Changes in features and parameters of a specified version as well as the affected entities
l
l Editorial changeEditorial change
Changes in wording or addition of information and any
Changes in wording or addition of information and any related parameters affrelated parameters affected byected by editorial changes. Editorial change does not
editorial changes. Editorial change does not specify the affected entities.specify the affected entities.
eRAN12.1 02 (2017-04-27)
eRAN12.1 02 (2017-04-27)
This issue includes the following changes. This issue includes the following changes.
C
Chhaanngge e TTyyppee CChhaanngge e DDeessccrriippttiioonn PPaarraammeetteerr Change Change
F
Feeaattuurreecchhaannggee NNoonnee NNoonnee
Editorial Editorial change change
Revised descriptions in
Revised descriptions in6.5 Performance Monitoring6.5 Performance Monitoring.. NNoonnee
eRAN12.1 01 (2017-03-08)
eRAN12.1 01 (2017-03-08)
This issue includes the following changes. This issue includes the following changes.
C
Chhaanngge e TTyyppee CChhaanngge e DDeessccrriippttiioonn PPaarraammeetteerr Change Change
F
Feeaattuurreecchhaannggee NNoonnee NNoonnee
Editorial Editorial change change
Revised descriptions in
Revised descriptions in6.4.2 Requirements6.4.2 Requirements.. NNoonnee
eRAN12.1 Draft A (2016-12-30)
eRAN12.1 Draft A (2016-12-30)
This document is created for eRAN12.1. This document is created for eRAN12.1. DL CoMP Feature Parameter Description
1.5 Differences Between eNodeB Types
1.5 Differences Between eNodeB Types
Feature Support by Macro, Micro, and LampSite eNodeBs
Feature Support by Macro, Micro, and LampSite eNodeBs
F
Feeaattuurre e IIDD FFeeaattuurre e NNaammee SSuuppppoorrtteed d bbyy Macro Macro eNodeBs eNodeBs Supported by Supported by Micro Micro eNodeBs eNodeBs Supported by Supported by LampSite LampSite eNodeBs eNodeBs LAOFD-12020 LAOFD-12020 1 1 DL CoMP DL CoMP (Trial) (Trial) Y Yeess NNoo YYeess
Feature Implementation in Macro and LampSite eNodeBs
Feature Implementation in Macro and LampSite eNodeBs
None None
DL CoMP Feature Parameter Description
22
Overview
Overview
2.1 Introduction
2.1 Introduction
In 3GPP releases earlier than 3GPP Release
In 3GPP releases earlier than 3GPP Release 11, physical downlink shared channel (PDSCH)11, physical downlink shared channel (PDSCH) data of LTE c
data of LTE cell edge usell edge users (CEUs) cannot be sent with the help ers (CEUs) cannot be sent with the help of adjacent cells to improveof adjacent cells to improve the performance of CEUs. This gain can be achieved by downlink coordinated multipoint the performance of CEUs. This gain can be achieved by downlink coordinated multipoint transmission (DL CoMP) based on TM10 introduced in 3GPP Release 11.
transmission (DL CoMP) based on TM10 introduced in 3GPP Release 11.
DL CoMP enables multiple cells to cooperate to perform downlink transmission. DL CoMP DL CoMP enables multiple cells to cooperate to perform downlink transmission. DL CoMP isis implemented based on TM10
implemented based on TM10 introduced in 3GPP Release 11. Multiple cells introduced in 3GPP Release 11. Multiple cells cooperate basedcooperate based on ideal backhaul (intra-BBU backhaul or
on ideal backhaul (intra-BBU backhaul or backhaul based on multi-BBU interconnectionbackhaul based on multi-BBU interconnection through USUs) to process and transmit PDSCH data by using antennas of
through USUs) to process and transmit PDSCH data by using antennas of neighboring cells.neighboring cells. USU refers to universal switching unit. Downlink transmission by multiple cells
USU refers to universal switching unit. Downlink transmission by multiple cells adopts twoadopts two modes, dynamic point selection (DPS) and joint transmission (JT), to improve hotspot modes, dynamic point selection (DPS) and joint transmission (JT), to improve hotspot cellcell capacity or CEU performance. eNodeBs can adaptively select an
capacity or CEU performance. eNodeBs can adaptively select an appropriate transmissionappropriate transmission mode based on t
mode based on the cell load and he cell load and channel qualitychannel quality..
DPS
DPS
In DPS mode, the coordinating cell sends PDSCH data to the
In DPS mode, the coordinating cell sends PDSCH data to the UE to increase the hotspot cellUE to increase the hotspot cell capacity
capacity, CEU , CEU throughput, and average UE throughput, and average UE throughput.throughput. Figure 2-1
Figure 2-1 illustrates the DPS mode, in illustrates the DPS mode, in which PDCCH data of the UE is sent which PDCCH data of the UE is sent by cell 1 (theby cell 1 (the serving cell), and PDSCH data is sent by cell
serving cell), and PDSCH data is sent by cell 1 to cell 2 1 to cell 2 (the coordinating cell) and then sent(the coordinating cell) and then sent by cell 2 to the UE.
by cell 2 to the UE. DL CoMP Feature Parameter Description
Figure 2-1 Figure 2-1 DPS DPS
JT
JT
In JT mode, both the
In JT mode, both the serving cell and coordinating cell transmit PDSCH data to improve theserving cell and coordinating cell transmit PDSCH data to improve the throughput of CEUs with a low
throughput of CEUs with a low signal to interference plus noise ratio (SINR).signal to interference plus noise ratio (SINR). Figure 2-2
Figure 2-2 illustrates the JT mode, in which illustrates the JT mode, in which
l
l PDCCH data of the UE is PDCCH data of the UE is sent by cell 1 (the sent by cell 1 (the serving cell), and PDSCH data is sent byserving cell), and PDSCH data is sent by cell 1 to cell 2
cell 1 to cell 2 (the coordinating cell). Cell 1 and cell 2 (the coordinating cell). Cell 1 and cell 2 allocate the same RBs to sendallocate the same RBs to send PDSCH data to the UE.
PDSCH data to the UE.
l
l The UE receives the same PDSCH data from cell 1 and cell The UE receives the same PDSCH data from cell 1 and cell 2 simultaneously2 simultaneously.. Figure 2-2
Figure 2-2 JT JT DL CoMP Feature Parameter Description
2.2 Benefits
2.2 Benefits
DL CoMP improves the downlink throughput and user experience of CEUs. DL CoMP improves the downlink throughput and user experience of CEUs.
l
l DPS increases the capacity of hotspot cells and improves the CEU throughput andDPS increases the capacity of hotspot cells and improves the CEU throughput and average UE throughput when the network load is heavy and imbalanced.
average UE throughput when the network load is heavy and imbalanced.
l
l JT improves the throughput of CEUs with JT improves the throughput of CEUs with a low SINR when the network load is a low SINR when the network load is light.light.
2.3 Related Concepts
2.3 Related Concepts
T
Table 2able 2-1-1 lists the concepts related to DL CoMP. lists the concepts related to DL CoMP. T
Table 2able 2-1-1 Related concepts Related concepts
C
Coonncceepptt DDeeffiinniittiioonn
Coordinating cell Coordinating cell set of the serving set of the serving cell
cell
A set of 10 neighboring cells t
A set of 10 neighboring cells that cause the strongest interference tohat cause the strongest interference to the serving cell as measured by the eNodeB
the serving cell as measured by the eNodeB
S
Seerrvviinng g sseellll A A sseerrvviinng cg ceelll il is ts thhe e cceelll tl thhaat Ut UEEs as acccceessss.. D
DPPS S UUEE TThhe e eeNNooddeeB B uussees s aallggoorriitthhmms s tto o ddeetteerrmmiinne e wwhheetthheer r a a UUE E mmeeeetts s tthhee DPS threshold conditions. The UE that meets the DPS threshold DPS threshold conditions. The UE that meets the DPS threshold conditions is a DPS UE.
conditions is a DPS UE.
JJT T UUEE TThhe e eeNNooddeeB B uussees s aallggoorriitthhmms s tto o ddeetteerrmmiinne e wwhheetthheer r a a UUE E mmeeeetts s tthhe e JJTT threshold conditions. The UE that meets the JT
threshold conditions. The UE that meets the JT threshold conditionsthreshold conditions is a JT UE. is a JT UE. Coordinating cell Coordinating cell of a DPS or JT UE of a DPS or JT UE
The eNodeB identifies the coordinating cells for a DPS or JT UE The eNodeB identifies the coordinating cells for a DPS or JT UE based on the event A
based on the event A3 measurement repo3 measurement report sent by the DPS or rt sent by the DPS or JT UE.JT UE. The coordinating cells of a UE belong to
The coordinating cells of a UE belong to the coordinating cell set of the coordinating cell set of the serving cell of the UE.
the serving cell of the UE. eX
eX2 i2 intntererfafacece WhWhen en USUSU-U-babasesed md mulultiti-B-BBU BU inintetercrcononnenectctioion in is us usesed, d, ththe ee eX2X2 interface is responsible for service coordination between eNodeBs. interface is responsible for service coordination between eNodeBs.
2.4 Architecture
2.4 Architecture
DL CoMP is implemented through the cooperation of the U2000,
DL CoMP is implemented through the cooperation of the U2000, USU, eNodeB, and UE.USU, eNodeB, and UE. Figure 2-3
Figure 2-3 to toFigure 2-5Figure 2-5 show the networking diagrams. If DL CoMP is show the networking diagrams. If DL CoMP is performed amongperformed among BBUs, time synchronization is required across the entire network.
BBUs, time synchronization is required across the entire network. Figure 2-3
Figure 2-3 N Networkingetworking diagram for intra-BBU diagram for intra-BBU DL CoMP (macro-macro/macro-micrDL CoMP (macro-macro/macro-microo networking)
networking)
DL CoMP Feature Parameter Description
Figure 2-4
Figure 2-4 Networking diagram for inter-BBU DL Networking diagram for inter-BBU DL CoMP (macro-macro networking)CoMP (macro-macro networking)
Figure 2-5
Figure 2-5 Networking diagram for inter-BBU DL Networking diagram for inter-BBU DL CoMP (macro-micro networking)CoMP (macro-micro networking)
T
Table 2able 2-2-2 describes the functions of the network elements (NEs) shown in describes the functions of the network elements (NEs) shown in Figure 2-3Figure 2-3 to to Figure 2-5
Figure 2-5.. T
Table 2able 2-2-2 NE functions NE functions
N
NEE FFuunnccttiioonn
U2
U2000000 UsUsed ed fofor r papararamemeteter r coconfnfigigururatatioion n anand d peperfrforormamancnce e momoninitotoriringng.. eNodeB
eNodeB ll Configures channel state information-reference signal (CSI-RS)Configures channel state information-reference signal (CSI-RS) resources of a cell.
resources of a cell.
l
l Maintains and manages the coordinating cell set of a cell.Maintains and manages the coordinating cell set of a cell.
l
l Determines whether a UE is a DPS or JT UE Determines whether a UE is a DPS or JT UE and configures TM10 for and configures TM10 for the UE.
the UE.
l
l Performs coordinated transmission based on DPS or JT UE attributes.Performs coordinated transmission based on DPS or JT UE attributes. UE
UE ll Reports air interface measurement information, including the referenceReports air interface measurement information, including the reference signal received power (RSRP) and CSI.
signal received power (RSRP) and CSI.
l
l Receives PDSCH data according to the DCI format 2D indication.Receives PDSCH data according to the DCI format 2D indication. DL CoMP Feature Parameter Description
33
Technical Description
Technical Description
Figure 3-1
Figure 3-1 shows the DL CoMP process, including selection of shows the DL CoMP process, including selection of a coordinating cell set,a coordinating cell set, selection of CoMP UEs and coordinating cells, and multi-cell coordinated transmission. selection of CoMP UEs and coordinating cells, and multi-cell coordinated transmission. Figure 3-1
Figure 3-1 DL CoMP process DL CoMP process DL CoMP Feature Parameter Description
3.1 Selection of a
3.1 Selection of a Coordinating Cell Set
Coordinating Cell Set
The eNodeB selects a coordinating cell set as follows: The eNodeB selects a coordinating cell set as follows: 1.
1. After After DL CoMDL CoMP is eP is enablenabled, the d, the eNodeNodeB seleB selects ects a coora coordinatdinating ceing cell set fll set for the or the serviservingng cell based on the neighboring cell information reported by UEs.
cell based on the neighboring cell information reported by UEs. The DL CoMP algorithm switch settings vary with
The DL CoMP algorithm switch settings vary with networking scenarios.networking scenarios.
Networki Networki ng ng Scenario Scenario Parameter Setting Parameter Setting H
HoommNNeett TThheeFDDHomNetDlCompSwitch(FDDHomNetDlCompSwitch)FDDHomNetDlCompSwitch(FDDHomNetDlCompSwitch) check box under the
check box under the CellAlgoSwitchCellAlgoSwitch.. DlCompSwitch DlCompSwitch parameter is parameter is selected.
selected. H
HeettNNeett TThheeFDDHetNetDlCompSwitch(FDDHetNetDlCompSwitch)FDDHetNetDlCompSwitch(FDDHetNetDlCompSwitch) check check box under the
box under theCellAlgoSwitchCellAlgoSwitch.. DlCompSwitch DlCompSwitch parameter is selected. parameter is selected. HomNet HomNet and and HetNet HetNet
Both of the preceding check boxes are selected. Both of the preceding check boxes are selected.
2
2.. TThhe e uusseer r sseetts s tthheeNCellDlRsrpMeasParaNCellDlRsrpMeasPara.. DlRsrpAutoNCe DlRsrpAutoNCellMeasSwitchllMeasSwitch parameter to parameter to ON(On)
ON(On) and the and theNCellDlRsrpMeasParaNCellDlRsrpMeasPara.. NCellDlRsrpMe NCellDlRsrpMeasA3Offset asA3Offset parameter to a parameter to a desired value.
desired value. 3.
3. By colBy collectilecting infng informatormation on ion on neighneighborinboring cellg cells that s that meet emeet event Avent A3 rep3 reporting orting condiconditionstions within a certain period, the eNodeB selects 10 neighboring cells that
within a certain period, the eNodeB selects 10 neighboring cells that cause the highestcause the highest interference to the serving cell
interference to the serving cell as the coordinating cell as the coordinating cell set for DL set for DL CoMPCoMP. If micro . If micro cellscells exist, the eNodeB preferentially selects micro cells (6 at most), and then
exist, the eNodeB preferentially selects micro cells (6 at most), and then selects macroselects macro cells to form a coordinating cell set.
cells to form a coordinating cell set.
3.2 Selection of CoMP UEs and Coordinating Cells
3.2 Selection of CoMP UEs and Coordinating Cells
After selecting the DPS or JT serving cell, the eNodeB selects coordinating cells and CoMP After selecting the DPS or JT serving cell, the eNodeB selects coordinating cells and CoMP UEs based on the preset load thresholds.
UEs based on the preset load thresholds.
3.2.1 Entering the DPS Mode
3.2.1 Entering the DPS Mode
The process for a UE to enter the
The process for a UE to enter the DPS mode is as follows:DPS mode is as follows: 1.
1. DPDPS seS servrvining ceg cell sell selelectctioion is trn is trigiggegerered.d. DL CoMP Feature Parameter Description
Figure 3-2
Figure 3-2 Triggering of DPS/JT serving cell Triggering of DPS/JT serving cell selectionselection
As shown in
As shown inFigure 3-2Figure 3-2, when the PRB usage of t, when the PRB usage of the serving cell is greater than thehe serving cell is greater than the threshold specified by the
threshold specified by theCellDlCompAlgo.CellDlCompAlgo. DpsServingCellD DpsServingCellDlPrbThd lPrbThd parameter and parameter and the serving cell is a
the serving cell is a macro cell, the eNodeB selects the serving cell as the DPS servingmacro cell, the eNodeB selects the serving cell as the DPS serving cell.
cell. 2.
2. The eThe eNodeB NodeB seleselects thcts the cele cells with ls with the stthe strongerongest RSRst RSRP in thP in the cooe coordinardinating cting cell seell set ast as coordinating cells.
coordinating cells.
If the RSRP value of a neighboring cell
If the RSRP value of a neighboring cell minus that of the serving cell of minus that of the serving cell of a UE is greater a UE is greater than or equal to the
than or equal to the coordinating cell RSRP threshold plus the coordinating cell RSRPcoordinating cell RSRP threshold plus the coordinating cell RSRP offset, the UE reports event A3. If the neighboring cell that meets
offset, the UE reports event A3. If the neighboring cell that meets the event A3 reportingthe event A3 reporting conditions belongs to the coordinating cell set, it
conditions belongs to the coordinating cell set, it is selected as a coordinating cell.is selected as a coordinating cell.
–
– In HomNet networking scenarios, the coordinating cell RSRP threshold is specifiedIn HomNet networking scenarios, the coordinating cell RSRP threshold is specified
by the
by theCellDlCompAlgo.CellDlCompAlgo. HomnetDpsCo HomnetDpsCoCellRsrpThd CellRsrpThd parameter, and only the parameter, and only the macro cells with the strongest RSRP in
macro cells with the strongest RSRP in the coordinating cell set can be selected asthe coordinating cell set can be selected as coordinating cells.
coordinating cells.
–
– In HetNet scenarios, the coordinating cell RSRP threshold is specified by theIn HetNet scenarios, the coordinating cell RSRP threshold is specified by the
CellDlCompAlgo.
CellDlCompAlgo. HetnetDpsCoC HetnetDpsCoCellRsrpThd ellRsrpThd parameter, and only the micro parameter, and only the micro cellscells with the strongest RSRP in the
with the strongest RSRP in the coordinating cell set can be selected as coordinatingcoordinating cell set can be selected as coordinating cells.
cells.
–
– In HomNet and HetNet hybrid networking scenarios, the micro cells with theIn HomNet and HetNet hybrid networking scenarios, the micro cells with the
strongest RSRP in the coordinating cell set are preferentially selected as strongest RSRP in the coordinating cell set are preferentially selected as coordinating cells.
coordinating cells.
NOTE NOTE
The system automatically configures the coordinating cell RSRP offset to prevent ping-pong The system automatically configures the coordinating cell RSRP offset to prevent ping-pong configuration of TM10 for UEs.
configuration of TM10 for UEs.
3.
3. ThThe ee eNoNodedeB sB selelecects ts DPDPS US UEsEs.. If the coordinating cells selected in
If the coordinating cells selected in 22 meet all of the meet all of the following conditions, the eNodeBfollowing conditions, the eNodeB selects the UEs as DPS UEs and configures the TM10 mode
selects the UEs as DPS UEs and configures the TM10 mode for them.for them.
–
– The PRB usage of the serving cell minus The PRB usage of the serving cell minus the PRB usage of a coordinating cell isthe PRB usage of a coordinating cell is
greater than the value of the
greater than the value of the CellDlCompAlgo.CellDlCompAlgo. DpsLoadDiffT DpsLoadDiffThd hd parameter. parameter.
–
– The number of UEs in RRC_CONNECTED mode in The number of UEs in RRC_CONNECTED mode in a coordinating cell divided bya coordinating cell divided by
the number of UEs in RRC_CONNECTED mode in
the number of UEs in RRC_CONNECTED mode in the serving cell is less than the serving cell is less than or or DL CoMP Feature Parameter Description
equal to the value of the
equal to the value of the CellDlCompAlgo.CellDlCompAlgo. DpsCoCellUserR DpsCoCellUserRatioThd atioThd parameter. parameter. The selected DPS UE is regarded as a UE in
The selected DPS UE is regarded as a UE in the coordinating cell.the coordinating cell.
–
– No PCI mod 3 conflict e No PCI mod 3 conflict exists between coordinating xists between coordinating cells and the serving ccells and the serving cell.ell.
3.2.2 Entering the JT Mode
3.2.2 Entering the JT Mode
The process for a UE to enter the
The process for a UE to enter the JT mode is as follows:JT mode is as follows: 1.
1. JT sJT sererviving cng celell sel selelectctioion is tn is tririggggerereded.. As shown in
As shown inFigure 3-2Figure 3-2, when the PRB usage of the , when the PRB usage of the serving cell is less than or serving cell is less than or equal toequal to the threshold specified by the
the threshold specified by theCellDlCompAlgo. JtServingCellDlPrbTCellDlCompAlgo. JtServingCellDlPrbThd hd parameter, the parameter, the eNodeB selects the serving cell as the JT
eNodeB selects the serving cell as the JT serving cell.serving cell. 2.
2. The eThe eNodeB NodeB seleselects thcts the cele cells with ls with the stthe strongerongest RSRst RSRP in thP in the cooe coordinardinating cting cell seell set ast as coordinating cells.
coordinating cells.
If the RSRP value of the neighboring cell minus
If the RSRP value of the neighboring cell minus that of the serving cell of a that of the serving cell of a UE is greater UE is greater than or equal to the value
than or equal to the value of theof theCellDlCompAlgoCellDlCompAlgo.. JtCoCellRsrpThd JtCoCellRsrpThd parameter plus the parameter plus the coordinating cell RSRP offset, the UE reports event A3. If the neighboring cell that coordinating cell RSRP offset, the UE reports event A3. If the neighboring cell that meets the event A3 reporting conditions belongs to the
meets the event A3 reporting conditions belongs to the coordinating cell set, it is selectedcoordinating cell set, it is selected as a coordinating cell.
as a coordinating cell.
–
– In HomNet networking scenarios, only the cells of the same type In HomNet networking scenarios, only the cells of the same type as the serving cellas the serving cell
and with the strongest RSRP in
and with the strongest RSRP in the coordinating cell set can be selected asthe coordinating cell set can be selected as coordinating cells.
coordinating cells.
–
– In HetNet networking scenarios, when the serving cell is a macro cell, only In HetNet networking scenarios, when the serving cell is a macro cell, only thethe
micro cells with the strongest RSRP in
micro cells with the strongest RSRP in the coordinating cell set can be selected asthe coordinating cell set can be selected as coordinating cells.
coordinating cells.
–
– In HomNet and HetNet hybrid networking scenarios, the cells with the strongestIn HomNet and HetNet hybrid networking scenarios, the cells with the strongest
RSRP in the coordinating cell set are preferentially selected as coordinating cells. RSRP in the coordinating cell set are preferentially selected as coordinating cells. However
However, when the serving cell is , when the serving cell is a micro cell, only micro cells can be a micro cell, only micro cells can be selected asselected as coordinating cells.
coordinating cells.
NOTE NOTE
The system automatically configures the coordinating cell RSRP offset to prevent ping-pong The system automatically configures the coordinating cell RSRP offset to prevent ping-pong configuration of TM10 for UEs.
configuration of TM10 for UEs.
3.
3. ThThe ee eNoNodedeB sB selelecects ts JT JT UEUEs.s. If the coordinating cells selected in
If the coordinating cells selected in 22 meet both of the meet both of the following conditions, the eNodeBfollowing conditions, the eNodeB selects the UEs as JT UEs
selects the UEs as JT UEs and configures the TM10 mode for them.and configures the TM10 mode for them.
–
– The PRB usage of a coordinating cell is The PRB usage of a coordinating cell is less than the value of theless than the value of the
CellDlCompAlgo.
CellDlCompAlgo. JtCoCellDlPrbThd JtCoCellDlPrbThd parameter. parameter.
–
– The spectral efficiency for the CQIs reported by the UEs is less than The spectral efficiency for the CQIs reported by the UEs is less than that for CQIs 5that for CQIs 5
and 8 in the
and 8 in the case of single-codeword transmission. For details about CQIs 5 and 8,case of single-codeword transmission. For details about CQIs 5 and 8, see Table 7.2.3-1 4-bit CQI Table and Table 7.2.3-2 4-bit CQI Table 2 in section see Table 7.2.3-1 4-bit CQI Table and Table 7.2.3-2 4-bit CQI Table 2 in section 7.2.3 "Channel Quality Indicator (CQI) definition" in 3GPP TS 36.213 V12.9.1. 7.2.3 "Channel Quality Indicator (CQI) definition" in 3GPP TS 36.213 V12.9.1.
3.2.3 Exiting the DPS or JT Mode
3.2.3 Exiting the DPS or JT Mode
If a DPS or JT UE
If a DPS or JT UE reports exit event A3, the eNodeB disables TM10 configuration for the UEreports exit event A3, the eNodeB disables TM10 configuration for the UE and configures the UE
and configures the UE as a common user.as a common user. DL CoMP Feature Parameter Description
3.3 Multi-Cell Coordinated Transmission
3.3 Multi-Cell Coordinated Transmission
After the eNodeB determines the DPS or JT serving cell based on t
After the eNodeB determines the DPS or JT serving cell based on t he downlink PRB usagehe downlink PRB usage threshold, the transmission mode used by the serving cell
threshold, the transmission mode used by the serving cell is also determined.is also determined. As shown in
As shown inFigure 3-3Figure 3-3, the eNodeB delivers two sets of , the eNodeB delivers two sets of CSI measurement configurations toCSI measurement configurations to a CoMP UE for measuring channel state information (CSI), including precoding matrix a CoMP UE for measuring channel state information (CSI), including precoding matrix indication (PMI), rank indication (RI), and CQI, of the serving and coordinating cells, indication (PMI), rank indication (RI), and CQI, of the serving and coordinating cells, respectively
respectively. The eNodeB transmits . The eNodeB transmits data in DPS or data in DPS or JT mode based on JT mode based on the CSI measurementthe CSI measurement results reported by the UE and the scheduling information of t
results reported by the UE and the scheduling information of t he serving and coordinatinghe serving and coordinating cells.
cells. Figure 3-3
Figure 3-3 CSI measurement configuration CSI measurement configuration DL CoMP Feature Parameter Description
44
Related Features
Related Features
Prerequisite Features
Prerequisite Features
F
Feeaattuurre e IIDD FFeeaattuurre e NNaammee DDeessccrriippttiioonn
LB
LBFDFD-0-003030000505033 SySyncnchrhrononizizatatioion n wiwithth GPS
GPS
If DL CoMP is performed among BBUs, If DL CoMP is performed among BBUs, time synchronization is required across the time synchronization is required across the entire network. Therefore, inter-BBU DL entire network. Therefore, inter-BBU DL CoMP requires either of these
CoMP requires either of these features.features. LO
LOFDFD-0-003030101303022 IEIEEEEE151588 V88 V2 Cl2 Clocock k Synchronization Synchronization
Mutually Exclusive Features
Mutually Exclusive Features
F
Feeaattuurre e IIDD FFeeaattuurre e NNaammee DDeessccrriippttiioonn
L
LBBFFDD--007700110066 PPDDSSCCH EH Effffiicciieennccyy Improvement Improvement
Adaptive CEU power allocation is Adaptive CEU power allocation is ineffective to DL CoMP UEs. ineffective to DL CoMP UEs. LO
LOFFD-D-000010100707 HHigigh Sh Spepeeed Md Moobibililityty IIn hn higigh sh spepeeed md mobobililitity sy sccenenararioios, s, ththe ce chahannnneell conditions and load status of a cell
conditions and load status of a cell change sochange so rapidly that DL CoMP cannot respond
rapidly that DL CoMP cannot respond promptly
promptly.. L
LOOFFDD--000011000088 UUllttrra a HHiiggh Sh Sppeeeedd Mobility
Mobility L
LOOFFDD--000011000099 EExxtteennddeed Cd Ceelll Al Acccceessss Radius
Radius
In DL CoMP, UEs need to receive data from In DL CoMP, UEs need to receive data from different cells simultaneously. Therefore, DL different cells simultaneously. Therefore, DL CoMP does not apply to extended coverage CoMP does not apply to extended coverage scenarios.
scenarios. L
LOOFFDD--000011003311 EExxtteennddeed d CCPP LA
LAOFOFD-D-080812123333 DyDynanamimic Tc TDM DM eIeICICICC BoBoth th DL DL CoCoMP MP anand ed enhnhananceced id intnterer-c-celelll interference coordination (eICIC) can offer interference coordination (eICIC) can offer macro-micro offload gains by using cell macro-micro offload gains by using cell range expansion (CRE). Because CEUs have range expansion (CRE). Because CEUs have been handed over
been handed over to the micro cell, enato the micro cell, enablingbling both DL CoMP and eI
both DL CoMP and eICIC will yieldCIC will yield negative gains.
negative gains. L
LAAOOFFDD--008811223344 FFeeIICCIICC DL CoMP Feature Parameter Description
F
Feeaattuurre e IIDD FFeeaattuurre e NNaammee DDeessccrriippttiioonn
L
LOOFFDD--006600220011 AAddaappttiivve Ine Intteerr--CCeellll Interference
Interference Coordination Coordination
Adaptive inter-cell interference coordination Adaptive inter-cell interference coordination (ICIC) is based on the eCoordinator
(ICIC) is based on the eCoordinator architecture. DL CoMP cannot obtain architecture. DL CoMP cannot obtain
frequency bands of neighboring cells. In this frequency bands of neighboring cells. In this case, DL CoMP cannot coordinate UEs to case, DL CoMP cannot coordinate UEs to neighboring cells for scheduling.
neighboring cells for scheduling. LA
LAOOFDFD-1-11112120404 AdaAdaptptivive SFe SFNN/S/SDMDMAA with TM10
with TM10 (Trial)(Trial)
The CSI-RS pattern of adaptive SFN/SDMA The CSI-RS pattern of adaptive SFN/SDMA is inconsistent with
is inconsistent with that of DL that of DL CoMPCoMP.. L
LEEOOFFDD--111111330055 VViirrttuuaal l 44TT44RR DL DL CCooMMP P iis s tteemmppoorraarriilly y nnoot t ssuuppppoorrtteed d iinn virtual 4T4R scenarios.
virtual 4T4R scenarios.
Impacted Features
Impacted Features
F
Feeaattuurre e IIDD FFeeaattuurree//FFuunnccttiioonn Name
Name
Description Description
L
LOOFFDD--000011001166 VVooIIP P SSeemmii--ppeerrssiisstteenntt Scheduling
Scheduling
Resource conflicts may occur between Resource conflicts may occur between semi- persistent scheduling and D
persistent scheduling and DL CoMPL CoMP
coordinating cell scheduling. Therefore, DL coordinating cell scheduling. Therefore, DL CoMP coordinating cell scheduling is not CoMP coordinating cell scheduling is not performed within the TT
performed within the TTI in which semi-I in which semi- persistent scheduling is ef
persistent scheduling is effective.fective. L
LOOFFDD--000022000055 MMoobbiilliitty y RRoobbuusstt Optimization (MRO) Optimization (MRO)
MRO may affect the optimal RSRP MRO may affect the optimal RSRP
threshold setting of coordinating cells in DL threshold setting of coordinating cells in DL CoMP
CoMP. As . As a result, a result, the cell-edge throughputthe cell-edge throughput across the entire network cannot reach the across the entire network cannot reach the optimal level that DL CoMP can achieve. optimal level that DL CoMP can achieve. L LBBFFDD--006600110033 EEnnhhaanncceed Dd DLL Frequency Selective Frequency Selective Scheduling Scheduling Frequency-sele
Frequency-selective scheduling can ctive scheduling can bebe performed for DL
performed for DL CoMP UEs only in theCoMP UEs only in the serving cell.
serving cell. L
LBBFFDD--000022001177 DDRRXX DDL L CCooMMP P mmaay y ffaaiil l tto o ttaakke e eeffffeecct t dduurriinngg coordinating cell scheduling in the DRX coordinating cell scheduling in the DRX sleep time. Therefore, the optimal DL CoMP sleep time. Therefore, the optimal DL CoMP performance ca
performance cannot be achieved.nnot be achieved. LO
LOFFD-D-0000111105050101 DDynynaamimic Dc DRXRX
LO
LOFFD-D-000010107070 SSymymbbol ol PPowoweer Sr Saavivingng WhWhen en boboth th DDL CL CooMP MP anand ed enhnhaancnced ed sysymbmbooll power saving are e
power saving are enabled, enhanced nabled, enhanced symbolsymbol power saving is not trigger
power saving is not triggered during DLed during DL CoMP coordinating cell scheduling. CoMP coordinating cell scheduling. L
LAAOOFFDD--111100220033 eePPDDCCCCH H ((TTrriiaall)) WhWheen n bbootth h DDL L CCooMMP P aannd d eePPDDCCCCH H aarree enabled, a UE configured with ePDCCH enabled, a UE configured with ePDCCH cannot be selected as a CoMP UE. As cannot be selected as a CoMP UE. As aa result, the optimal DL CoMP performance result, the optimal DL CoMP performance cannot be achieved.
cannot be achieved. DL CoMP Feature Parameter Description
F
Feeaattuurre e IIDD FFeeaattuurree//FFuunnccttiioonn Name
Name
Description Description
L
LBBFFDD--000022002288 EEmmeerrggeennccy y CCaallll UUEEs s mmaakkiinng g eemmeerrggeennccy y ccaalllls s ccaannnnoot t bbee selected as CoMP UEs. As a result, the selected as CoMP UEs. As a result, the optimal DL CoMP performance cannot be optimal DL CoMP performance cannot be achieved.
achieved. N/A
N/A Carrier aggregCarrier aggregationation (CA)
(CA)
For DL CoMP, TM10 is configured only in For DL CoMP, TM10 is configured only in the PCell, not in t
the PCell, not in t he SCell. Therefore, onlyhe SCell. Therefore, only the data in the PCell
the data in the PCell can be scheduled in thecan be scheduled in the coordinating cell.
coordinating cell. L
LOOFFDD--007700220088 CCoooorrddiinnaatteedd Scheduling based Scheduling based Power Control Power Control
l
l DL CoMP can be enabled when theDL CoMP can be enabled when the CellCSPCPara.
CellCSPCPara.CellCspcSwitchCellCspcSwitch parameter is set to O
parameter is set to ON(On), andN(On), and coordinated scheduling-based power coordinated scheduling-based power control (CSPC) takes
control (CSPC) takes effecteffect preferentially
preferentially. If CSPC has taken . If CSPC has taken effect ineffect in a cell, DL CoMP UEs are not
a cell, DL CoMP UEs are not scheduledscheduled in coordinating cells.
in coordinating cells.
l
l DL CoMP cannot be enabled when theDL CoMP cannot be enabled when the CellCSPCPara.
CellCSPCPara.CelleCspcSwitchCelleCspcSwitch parameter is set to
parameter is set toON(On)ON(On).. L
LOOFFDD--000033002299 SSFFNN ll In single frequency network (SFN)In single frequency network (SFN) scenarios, if antennas of physical scenarios, if antennas of physical cellscells are configured in mixed mode, DL CoMP are configured in mixed mode, DL CoMP does not function between SFN cells. does not function between SFN cells.
l
l In inter-BBU SFN scenarios, SFN cellsIn inter-BBU SFN scenarios, SFN cells do not support DL CoMP.
do not support DL CoMP. L
LOOFFDD--007700220055 AAddaappttiivve e SSFFNN//SSDDMMAA ll DL CoMP and adaptive DL CoMP and adaptive SFN/SDMA canSFN/SDMA can be enabled at the s
be enabled at the same time. Howeverame time. However,, only the joint scheduling mode can be only the joint scheduling mode can be used for CoMP UEs in coordinating cells used for CoMP UEs in coordinating cells because no RSRP
because no RSRP information aboutinformation about RRUs serving neighboring cells is RRUs serving neighboring cells is available and UE attributes cannot be available and UE attributes cannot be determined.
determined.
l
l DL CoMP cannot be enabled whenDL CoMP cannot be enabled when adaptive SFN/SDMA in TM9 is
adaptive SFN/SDMA in TM9 is enabled.enabled.
l
l In SFN scenarios, if antennas of In SFN scenarios, if antennas of physicalphysical cells are configured in mixed mode, DL cells are configured in mixed mode, DL CoMP does not function between SFN CoMP does not function between SFN cells.
cells.
l
l In inter-BBU SFN scenarios, SFN cellsIn inter-BBU SFN scenarios, SFN cells do not support DL CoMP.
do not support DL CoMP. DL CoMP Feature Parameter Description
55
Network Impact
Network Impact
System Capacity
System Capacity
DL CoMP is implemented using TM10. CSI-RSs need to
DL CoMP is implemented using TM10. CSI-RSs need to be configured (in thebe configured (in the CellCsiRsParaCfg
CellCsiRsParaCfg MO) in cells when DL MO) in cells when DL CoMP is enabled. However, CSI-RSs will result inCoMP is enabled. However, CSI-RSs will result in a loss of system capacity. The more REs occupied by CSI-RSs indicate the shorter subframe a loss of system capacity. The more REs occupied by CSI-RSs indicate the shorter subframe period and greater
period and greater loss.loss.
Network Performance
Network Performance
DL CoMP has the following impact on
DL CoMP has the following impact on network performance:network performance:
l
l When DPS takes effect, PDSCH data of CEUs in the heavily loaded serving cell areWhen DPS takes effect, PDSCH data of CEUs in the heavily loaded serving cell are offloaded to coordinating cells. In this
offloaded to coordinating cells. In this wayway, more resources are available for , more resources are available for UEs in theUEs in the serving cell, and the user-perceived downlink throughput in the serving cell increases. If serving cell, and the user-perceived downlink throughput in the serving cell increases. If the increase of resources for DPS UEs in the lightly loaded coordinating cells cannot the increase of resources for DPS UEs in the lightly loaded coordinating cells cannot compensate for the loss
compensate for the loss of channel quality deterioration, the of channel quality deterioration, the user-percuser-perceived downlink eived downlink throughput of the
throughput of the DPS UEs decreases.DPS UEs decreases.
l
l HomNet networking: When the PRB usage of the heavily loaded cell is HomNet networking: When the PRB usage of the heavily loaded cell is 60%, DL CoMP60%, DL CoMP increases the CEU throughput by 5% to 10%
increases the CEU throughput by 5% to 10% and the average UE throughput by up toand the average UE throughput by up to 5%.
5%.
l
l HetNet networking: When a macro cell includes four micro cells and the PRB HetNet networking: When a macro cell includes four micro cells and the PRB usage of usage of
the macro cell is 60%, DL CoMP
the macro cell is 60%, DL CoMP increases the CEU throughput by about 20% and theincreases the CEU throughput by about 20% and the average UE throughput by about 10%.
average UE throughput by about 10%.
l
l When the PRB usage of a cell When the PRB usage of a cell is 10%, DL CoMP increases the throughput of JT is 10%, DL CoMP increases the throughput of JT UEs byUEs by about 10%. The CEU throughput increase depends on the ratio of
about 10%. The CEU throughput increase depends on the ratio of JT UEs to CEUs. If JT UEs to CEUs. If both the DL CoMP and CS
both the DL CoMP and CSI-RS switches are I-RS switches are turned on when there turned on when there are a few JT Uare a few JT UEs,Es, CSI-RS subframe configuration will decrease the average UE throughput.
CSI-RS subframe configuration will decrease the average UE throughput.
l
l DL CoMP uses more PRB resources to increase the average PRB usage, increasingDL CoMP uses more PRB resources to increase the average PRB usage, increasing interference of neighboring cells. In this case, the measured CQI value and the interference of neighboring cells. In this case, the measured CQI value and the proportion of rank 2 of
proportion of rank 2 of CEUs may decrease CEUs may decrease slightlyslightly..
l
l When theWhen theUnCfgCsiRsUEDeOrderSchSwitch(UnCfgCsiRsUEDeOrderSchSwitch)UnCfgCsiRsUEDeOrderSchSwitch(UnCfgCsiRsUEDeOrderSchSwitch) check box under the
check box under theCellDlschAlgoCellDlschAlgo..CsiRsSfSchStrSwitchCsiRsSfSchStrSwitch parameter is cleared, UEs not parameter is cleared, UEs not supporting TM9 or TM10 are not scheduled in
supporting TM9 or TM10 are not scheduled in CSI-RS subframes. The perceivedCSI-RS subframes. The perceived throughput of such UEs will decrease by 0% to
throughput of such UEs will decrease by 0% to 5%. When this check box is selected,5%. When this check box is selected, UEs not supporting TM9 or TM10
UEs not supporting TM9 or TM10 can be scheduled in CSI-RS subframes by usingcan be scheduled in CSI-RS subframes by using lower MCS indexes. The perceived throughput of such UEs will increase by 0% to lower MCS indexes. The perceived throughput of such UEs will increase by 0% to 3%.3%. DL CoMP Feature Parameter Description
66
Engineering Guidelines
Engineering Guidelines
6.1 When to Use
6.1 When to Use
Y
You are advised to enable DL CoMP when all ou are advised to enable DL CoMP when all of the following conditions are met:of the following conditions are met:
l
l The average inter-RRU distance is less than 500 m in The average inter-RRU distance is less than 500 m in densely populated urban areas.densely populated urban areas.
l
l The average downlink PRB usage of hotspot cells is The average downlink PRB usage of hotspot cells is greater than 40% in heavy-loadgreater than 40% in heavy-load scenarios. This condition is more easily met in
scenarios. This condition is more easily met in macro-micro networking scenamacro-micro networking scenarios.rios.
l
l The average downlink PRB usage of cells is less The average downlink PRB usage of cells is less than 20% in light-load scenarios.than 20% in light-load scenarios.
l
l Most UEs move at a Most UEs move at a speed lower than 10 km/h.speed lower than 10 km/h.
l
l The penetration rate of TM10-capable UEs exceeds 70%.The penetration rate of TM10-capable UEs exceeds 70%.
6.2 Required Information
6.2 Required Information
T
To accurately evaluate whether the conditions for o accurately evaluate whether the conditions for enabling DL CoMP are met, enabling DL CoMP are met, collect thecollect the following information before feature deployment:
following information before feature deployment:
l
l Penetration rate of TM10-capable UEsPenetration rate of TM10-capable UEs Check whether UEs on
Check whether UEs on the network support TM10 the network support TM10 based on the based on the supportedCSIProcsupportedCSIProcr11r11 field in the external CHR event PRIVATE_UE_CAPABILITY_INFORMATION and field in the external CHR event PRIVATE_UE_CAPABILITY_INFORMATION and evaluate the penetration rate of
evaluate the penetration rate of TM10-capable UEs.TM10-capable UEs.
l
l Engineering parameters of cellsEngineering parameters of cells
–
– Frequency and bandwidth configurations of cellsFrequency and bandwidth configurations of cells –
– Inter-site distance and longitude and latitude of each siteInter-site distance and longitude and latitude of each site
l
l LTE network load, interference, and coverage performanceLTE network load, interference, and coverage performance
NOTE NOTE
Among the following listed counters, counters related to CEUs are available only when the Among the following listed counters, counters related to CEUs are available only when the BasedA3EdgeUserSwitch(BasedA3EdgeUserSwitch)
BasedA3EdgeUserSwitch(BasedA3EdgeUserSwitch) check box under the check box under the CellCounterParaGroup
CellCounterParaGroup..CellCounterAlgoSwitchCellCounterAlgoSwitch parameter is selected. CEUs can be identified parameter is selected. CEUs can be identified based on th
based on thee CellCounterParaGroupCellCounterParaGroup.. EdgeUserA3Offset EdgeUserA3Offset parameter. CEUs with weak coverage parameter. CEUs with weak coverage can be identified based on the
can be identified based on the CellCounterParaGroupCellCounterParaGroup.. EdgeUserServRSRPThd EdgeUserServRSRPThd parameter. parameter.
DL CoMP Feature Parameter Description
–
– Network load is indicate Network load is indicated by the counters listed ind by the counters listed inTable 6-1Table 6-1 and andTable 6-2Table 6-2..
T
Table able 6-16-1 Counters related to the number of users in Counters related to the number of users in a cella cell
Counter Counter ID ID
C
Coouunntteer r NNaammee DDeessccrriippttiioonn
152672737 152672737 8
8
L.Traffic.User.Avg
L.Traffic.User.Avg Average number of usersAverage number of users in a cell in a cell 152672737 152672737 9 9 L.Traffic.User.Max
L.Traffic.User.Max Maximum number of Maximum number of users in a cell users in a cell 152672896 152672896 9 9 L.Traffic.ActiveUser.DL.Avg
L.Traffic.ActiveUser.DL.Avg Average number of Average number of active users in the active users in the downlink downlink 152672897 152672897 0 0 L.Traffic.ActiveUser.DL.Max
L.Traffic.ActiveUser.DL.Max Maximum number of Maximum number of active users in the active users in the downlink downlink 152672897 152672897 5 5 L.Traffic.ActiveUser.Avg
L.Traffic.ActiveUser.Avg Average number of Average number of active users active users 152672897 152672897 6 6 L.Traffic.ActiveUser.Max
L.Traffic.ActiveUser.Max Maximum number of Maximum number of active users
active users
T
Table able 6-26-2 Counters related to the average number of PRBs used in Counters related to the average number of PRBs used in the downlink the downlink
Counter Counter ID ID
C
Coouunntteer r NNaammee DDeessccrriippttiioonn
152672674 152672674 0
0
L.ChMeas.PRB.DL.Used.Avg
L.ChMeas.PRB.DL.Used.Avg Average number of usedAverage number of used downlink PRBs downlink PRBs 152674176 152674176 7 7 L.ChMeas.PRB.PDSCH.Avg.Border L.ChMeas.PRB.PDSCH.Avg.Border UE UE
Average number of Average number of PDSCH PRBs occupied PDSCH PRBs occupied by CEUs in a cell by CEUs in a cell
–
– Network interfere Network interference and coverance and coverage performance ge performance are indicated by the are indicated by the counters listedcounters listed
in
inTTable 6able 6-3-3 to toTable 6-8Table 6-8.. T
Table able 6-36-3 Counters related to the number of CEUs Counters related to the number of CEUs in a cellin a cell
Counter Counter ID ID
C
Coouunntteer r NNaammee DDeessccrriippttiioonn
152674188 152674188 8
8
L.Traffic.User.BorderUE.Avg
L.Traffic.User.BorderUE.Avg Average number of Average number of CEUs in a cell CEUs in a cell 152674188 152674188 9 9 L.Traffic.User.BorderUE.Max
L.Traffic.User.BorderUE.Max Maximum number of Maximum number of CEUs in a cell
CEUs in a cell DL CoMP Feature Parameter Description
T
Table able 6-46-4 Counters related to the number of times Counters related to the number of times each MCS index is selected for each MCS index is selected for PDSCH scheduling PDSCH scheduling Counter Counter ID ID C
Coouunntteer r NNaammee DDeessccrriippttiioonn
152672744 152672744 4 to 4 to 152672747 152672747 5 5 L.ChMeas.PDSCH.MCS.0 L.ChMeas.PDSCH.MCS.0 to to L.ChMeas.PDSCH.MCS.31 L.ChMeas.PDSCH.MCS.31 Number of times MCS Number of times MCS index index N N ( ( N N = 0 to 31) is = 0 to 31) is selected for PDSCH selected for PDSCH scheduling scheduling T
Table able 6-56-5 Counters related to the number of times Counters related to the number of times full bandwidth CQIs 0 to full bandwidth CQIs 0 to 15 are15 are reported in a cell reported in a cell Counter Counter ID ID C
Coouunntteer r NNaammee DDeessccrriippttiioonn
152672739 152672739 6 to 6 to 152672741 152672741 1 1 L.ChMeas.CQI.DL.0 L.ChMeas.CQI.DL.0 to to L.ChMeas.CQI.DL.15 L.ChMeas.CQI.DL.15
Number of times full Number of times full bandwidth CQI
bandwidth CQI N N ( ( N N = 0 = 0 to 15) is reported over to 15) is reported over the air interface
the air interface 152673771
152673771 0
0
L.ChMeas.CQI.DL.BorderUE.Total
L.ChMeas.CQI.DL.BorderUE.Total Accumulated value of Accumulated value of full bandwidth CQIs full bandwidth CQIs reported by CEUs reported by CEUs 152673771 152673771 1 1 L.ChMeas.CQI.DL.BorderUE.Num
L.ChMeas.CQI.DL.BorderUE.Num Number of times full Number of times full bandwidth CQIs are bandwidth CQIs are
reported by CEUs reported by CEUs
T
Table able 6-66-6 Counters related to the number of times Counters related to the number of times ranks 1 to 4 ranks 1 to 4 are reported by UEsare reported by UEs in a cell in a cell Counter Counter ID ID C
Coouunntteer r NNaammee DDeessccrriippttiioonn
152673014 152673014 1
1
L.ChMeas.RI.Rank1
L.ChMeas.RI.Rank1 Number of times a U Number of times a UEE reports rank 1 reports rank 1 152673014 152673014 2 2 L.ChMeas.RI.Rank2
L.ChMeas.RI.Rank2 Number of times a U Number of times a UEE reports rank 2 reports rank 2 152673273 152673273 7 7 L.ChMeas.RI.Rank3
L.ChMeas.RI.Rank3 Number of times a U Number of times a UEE reports rank 3 reports rank 3 152673273 152673273 8 8 L.ChMeas.RI.Rank4
L.ChMeas.RI.Rank4 Number of times a U Number of times a UEE reports rank 4
reports rank 4 DL CoMP Feature Parameter Description
T
Table able 6-76-7 Counters related to the average downlink rate of UEs in Counters related to the average downlink rate of UEs in a cella cell
Counter Counter ID ID
C
Coouunntteer r NNaammee DDeessccrriippttiioonn
152672826 152672826 1
1
L.Thrp.bits.DL
L.Thrp.bits.DL Total volume of Total volume of downlink data downlink data transmitted at the PDCP transmitted at the PDCP layer in a cell layer in a cell 152672899 152672899 7 7 L.Thrp.Time.Cell.DL.HighPrecision
L.Thrp.Time.Cell.DL.HighPrecision Total duration of Total duration of downlink data downlink data
transmission in a cell transmission in a cell (with the precision of 1 (with the precision of 1 ms) ms) 152672826 152672826 2 2 L.Thrp.Time.DL
L.Thrp.Time.DL Total duration of Total duration of downlink data downlink data transmission at the transmission at the PDCP layer in a cell PDCP layer in a cell 152672900 152672900 5 5 L.Thrp.bits.DL.LastTTI
L.Thrp.bits.DL.LastTTI Downlink traffic volumeDownlink traffic volume for PDCP SDUs sent in for PDCP SDUs sent in the last TTI before the the last TTI before the buffer is empty buffer is empty 152672901 152672901 5 5 L.Thrp.Time.DL.RmvLastTTI
L.Thrp.Time.DL.RmvLastTTI Data transmissionData transmission duration except the last duration except the last TTI before the downlink TTI before the downlink buffer is empty
buffer is empty
T
Table able 6-86-8 Counters related to the downlink rate of Counters related to the downlink rate of CEUs in a cellCEUs in a cell
Counter Counter ID ID
C
Coouunntteer r NNaammee DDeessccrriippttiioonn
152673775 152673775 5
5
L.Thrp.bits.DL.BorderUE
L.Thrp.bits.DL.BorderUE Total downlink trafficTotal downlink traffic volume of PDCP SDUs volume of PDCP SDUs for CEUs in a cell for CEUs in a cell 152674176
152674176 0
0
L.Thrp.Time.DL.BorderUE
L.Thrp.Time.DL.BorderUE Total duration of sendingTotal duration of sending data to CEUs in the data to CEUs in the downlink at the PDCP downlink at the PDCP layer in a cell layer in a cell 152673775 152673775 8 8 L.Thrp.bits.DL.LastTTI.BorderUE
L.Thrp.bits.DL.LastTTI.BorderUE Downlink PDCP-layer Downlink PDCP-layer traffic volume sent in the traffic volume sent in the last TTI for CEUs before last TTI for CEUs before the buffer is empty in a the buffer is empty in a cell
cell DL CoMP Feature Parameter Description
Counter Counter ID ID
C
Coouunntteer r NNaammee DDeessccrriippttiioonn
152673775 152673775 9 9 L.Thrp.Time.DL.RmvLastTTI.Bord L.Thrp.Time.DL.RmvLastTTI.Bord erUE erUE Data transmission Data transmission duration for CEUs duration for CEUs except the last TTI except the last TTI before the downlink before the downlink buffer is empty buffer is empty
6.3 Planning
6.3 Planning
6.3.1 RF Planning
6.3.1 RF Planning
N/A N/A6.3.2 Network Planning
6.3.2 Network Planning
ll If inter-BBU DL CoMP is used, Cloud BB If inter-BBU DL CoMP is used, Cloud BB achieved by USU-based multi-BBUachieved by USU-based multi-BBU interconnection must be deployed in
interconnection must be deployed in advance.advance.
–
– For details about Cloud BB networking, seeFor details about Cloud BB networking, see Cloud BB Cloud BB Overview Feature Parameter Overview Feature Parameter
Description Description..
–
– For details about the networking, cable connections, and time synchronization for For details about the networking, cable connections, and time synchronization for
USU3910-based multi-BBU interconnection, see
USU3910-based multi-BBU interconnection, see USU3910-based Multi-BBU USU3910-based Multi-BBU Interconne
Interconnection Feature ction Feature Parameter DescriptionParameter Description..
l
l eNodeBs provide contiguous coverage with the eNodeBs provide contiguous coverage with the same frequency and bandwidth. The cellsame frequency and bandwidth. The cell bandwidth must be greate
bandwidth must be greater than or equal to 5 MHr than or equal to 5 MHz.z.
l
l If inter-BBU DL CoMP is used, time synchronization is required across the entireIf inter-BBU DL CoMP is used, time synchronization is required across the entire network. The time synchronization accuracy between all cells with DL CoMP to be network. The time synchronization accuracy between all cells with DL CoMP to be enabled must be less than 3
enabled must be less than 3 μs, and GPS or IEEE1588 V2 synchronization can be used.μs, and GPS or IEEE1588 V2 synchronization can be used. For details about time synchronization, see
For details about time synchronization, see SynchroSynchronization nization Feature Parameter Feature Parameter Description Description..
6.3.3 Hardware Planning
6.3.3 Hardware Planning
N/A N/A6.4 Deployment
6.4 Deployment
6.4.1 Process
6.4.1 Process
The DL CoMP deployment process is as follows: The DL CoMP deployment process is as follows: 1.
1. EnablEnable ae automautomatic mtic measueasuremerement of nt of neighneighborinboring ceg cell doll downlinwnlink RSk RSRPRP.. DL CoMP Feature Parameter Description
6.4.2 Requirements
6.4.2 Requirements
Other Features
Other Features
For details, see
For details, see4 Related Features4 Related Features..
Hardware
Hardware
l
l Baseband processing unit: The LBBPc does not support this Baseband processing unit: The LBBPc does not support this feature.feature.
l
l USU: A USU3910 is required when inter-BBU DL CoMP is to be USU: A USU3910 is required when inter-BBU DL CoMP is to be enabled.enabled.
l
l RRU: Low-power RRUs, such as mRRU3220E and mRRU3230E, which do RRU: Low-power RRUs, such as mRRU3220E and mRRU3230E, which do not supportnot support 1T1R or 1T2R,
1T1R or 1T2R, are used for micro cells are used for micro cells involved in DL involved in DL CoMPCoMP..
License
License
None NoneOther Requirements
Other Requirements
This feature requires support from UEs. UEs must be compliant with
This feature requires support from UEs. UEs must be compliant with 3GPP Release 11 or 3GPP Release 11 or later and capable of TM10
later and capable of TM10 multi-CSI measurement.multi-CSI measurement.
6.4.3 Precautions
6.4.3 Precautions
l
l All cells with DL CoMP All cells with DL CoMP enabled must have the same DL CoMP configurations.enabled must have the same DL CoMP configurations.
l
l DL CoMP is implemented using TM10. CSI-RSs must DL CoMP is implemented using TM10. CSI-RSs must be configured (in thebe configured (in the CellCsiRsParaCfg
CellCsiRsParaCfg MO) in all MO) in all involved cells when DL CoMP is enabled.involved cells when DL CoMP is enabled.
6.4.4 Hardware Adjustment
6.4.4 Hardware Adjustment
N/A N/A
6.4.5 Data Preparation and Feature Activation
6.4.5 Data Preparation and Feature Activation
6.4.5.1 Data Preparation
6.4.5.1 Data Preparation
DL CoMP based on USU3910-based multi-BBU interconnection requires that eX2 links be DL CoMP based on USU3910-based multi-BBU interconnection requires that eX2 links be configured. For parameters related to eX2 link
configured. For parameters related to eX2 link configuration, seeconfiguration, see eX2 Self-Management eX2 Self-Management Feature Pa
Feature Parameter Descriptionrameter Description..
The following table describes the parameter that must be set in
The following table describes the parameter that must be set in thethe CellAlgoSwitchCellAlgoSwitch MO to MO to enable DL CoMP.
enable DL CoMP. DL CoMP Feature Parameter Description
